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diff --git a/railties/doc/guides/actionview/helpers.markdown b/railties/doc/guides/actionview/helpers.markdown
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+Helpers
+====================
+
+Helper Basics
+------------------------
+
+Helpers allow you to encapsulate rendering tasks as reusable functions.  Helpers are modules, not classes, so their methods execute in the context in which they are called. They get included in a controller (typically the ApplicationController) using the helper function, like so
+
+	Class ApplicationController < ActionController::Base
+		…
+		helper :menu
+
+		def …
+		end
+	end
+
+In this way, methods in the menu helper are made available to any view or partial in your application. These methods can accept parameters, for example controller instance variables (eg; records or record collections gathered by you current controller), items from the view or partial’s locals[] hash or items from the params[] hash. You may wish to pass your controller instance variables and items from the params[] hash to the locals hash before rendering (See the section on partials). Helper methods can also accept an executable block of code.
+
+It is important to remember, though, that helpers are for rendering, and that they become available once a controller method has returned, while Rails is engaged in rendering the contents generated by a controller method. This means that helper methods are not available from within the methods of your controllers.
+
+Helpers can accomplish a variety of tasks, from formatting a complex tag for embedding content for a browser plugin (eg; Flash), to assembling a menu of options appropriate for the current context of your application, to generating sections of forms that get assembled on-the-fly.
+
+Helpers are organized around rendering tasks, so it is not necessary (nor necessarily desirable) to organize them around your application’s controllers or models. In fact, one of the benefits of helpers is that they are not connected via a rendering pipeline to specific controllers, like views and partials are. They can and should handle more generalized tasks.
+
+Here is a very simple, pseudo-example:
+
+	module  MenuHelper
+		def menu(records, menu_options={})
+			item_options = menu_options.merge({<some stuff>})
+			items = records.collect |record| do
+				menu_item(record, options)
+			end
+			content_tag(“ul”, items, options)
+		end
+
+		def menu_item(record, item_options={}))
+			action = item_options[:action]
+			action ||= “show”
+			content_tag(“li”, link_to(record.title, :action => action, item_options)
+		end
+	end
+
+
+This helper will require that records passed into it have certain fields (notably :title). The helper could be written to use this as a default, allowing the field to be overwritten by an element of item_options.
+
+Look at the Rails API for examples of helpers included in Rails, eg; [`ActionView::Helpers::ActiveRecordHelper`](http://api.rubyonrails.org/classes/ActionView/Helpers/ActiveRecordHelper.html).
+
+Passing Blocks to Helper Methods
+------------------------
+
+We mentioned before that blocks can be passed to helper methods. This allows for an interesting wrinkle: a block passed to a helper method can cause it to render a partial, which can then be wrapped by the helper method’s output. This can make your helper method much more reusable. It doesn’t need to know anything about the internals about what it is rendering, it just contextualizes it for the page. You can also use the helper to modify the locals hash for the partial, based on some configuration information unique to the current controller. You could implement a flexible themes system in this way.
+
+
+Partials vs. Helpers?
+------------------------
+
+In general, the choice between using a partial vs. using a helper depends on the amount of flexibility you need. If the task is more about reacting to conditions than performing actual rendering, you may likely want a helper method. If you want to be able to call it from a variety of views, again, you may want to use a helper method. You can expect to extract helper methods out of code in views and partials during refactoring.
+
+
+Tutorial -- Calling a Helper [UNFINISHED]
+------------------------
+
+1. Create a Rails application using `rails helper_test`
+Notice the code:
+
+		class ApplicationController < ActionController::Base
+			helper :all # include all helpers, all the time
+For this tutorial, we'll keep this code, but you will likely want to exert more control over loading your helpers.
+
+2. Configure a database of your choice for the app.
+
+3. Inside of the `/app/helpers/` directory, create a new file called, `menu_helper.rb`. Write this in the file:
+
+		module  MenuHelpers
+		   def menu(records, item_proc=nil)
+		      items = records.collect{ |record|
+		        menu_item(record, item_proc)
+		      }
+		      content_tag("ul", items)
+		   end
+
+		   def menu_item(record, item_proc=nil)
+		      item_url = item_proc.call(record)
+		      item_url ||= { :action => :show }
+		      content_tag("li", link_to(record.name, item_url))
+		   end
+		end
+
+4. Create a scaffold for some object in your app, using `./script/generate scaffold widgets`.
+5. Create a database table for your widgets, with at least the fields `name` and `id`. Create a few widgets.
+6. Call the menu command twice from `index.html.erb`, once using the default action, and once supplying a Proc to generate urls.
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diff --git a/railties/doc/guides/actionview/partials.markdown b/railties/doc/guides/actionview/partials.markdown
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+A Guide to Using Partials
+===============================
+
+This guide elaborates on the use and function of partials in Ruby on Rails. As your Rails application grows, your view templates can start to contain a lot of duplicate view code. To manage and reduce this complexity, you can by abstract view template code into partials. Partials are reusable snippets of eRB template code stored in separate files with an underscore ('_') prefix.
+
+Partials can be located anywhere in the `app/views` directory. File extensions for partials work just like other template files, they bear an extension that denotes what kind of code they generate. For example, `_animal.html.erb` and `_animal.xml.erb` are valid filenames for partials.
+
+Partials can be inserted in eRB template code by calling the `render` method with the `:partial` option. For example:
+
+	<%= render :partial => 'foo' %>
+
+This inserts the result of evaluating the template `_foo.html.erb` into the parent template file at this location. Note that `render` assumes that the partial will be in the same directory as the calling parent template and have the same file extension. Partials can be located anywhere within the `app/views` directory. To use a partial located in a different directory then it the parent, add a '/' before it:
+
+	<%= render :partial => '/common/foo' %>
+
+Loads the partial file from the `app/views/common/_foo.html.erb` directory.
+
+Abstracting views into partials can be approached in a number of different ways, depending on the situation. Sometimes, the code that you are abstracting is a specialized view of an object or a collection of objects. Other times, you can look at partials as a reusable subroutine. We'll explore each of these approaches and when to use them as well as the syntax for calling them.
+
+Partials as a View Subroutine
+-----------------------------
+
+Using the `:locals` option, you can pass a hash of values which will be treated as local variables within the partial template.
+
+	<%= render :partial => "person", :locals => { :name => "david" } %>
+
+The variable `name` contains the value `"david"` within the `_person.html.erb` template. Passing variables in this way allows you to create modular, reusable template files. Note that if you want to make local variables that are optional in some use cases, you will have to set them to a sentinel value such as `nil` when they have not been passed. So, in the example above, if the `name` variable is optional in some use cases, you must set:
+
+	<% name ||= nil -%>
+
+So that you can later check:
+
+	<% if name -%>
+		<p>Hello, <%= name %>!</p>
+	<% end -%>
+
+Otherwise, the if statement will throw an error at runtime.
+
+Another thing to be aware of is that instance variables that are visible to the parent view template are visible to the partial. So you might be tempted to do this:
+
+	<%= render :partial => "person" %>
+
+And then within the partial:
+
+	<% if @name -%>
+		<p>Hello, <%= @name %>!</p>
+	<% end -%>
+
+The potential snag here is that if multiple templates start to rely on this partial, you will need to maintain an instance variable with the same name across all of these templates and controllers. This approach can quickly become brittle if overused.
+
+Partials as a View of an Object
+--------------------------------
+
+Another way to look at partials is to view them as mini-views of a particular object or instance variable. Use the `:object` option to pass an object assigns that object to an instance variable named after the partial itself. For example:
+
+	# Renders the partial, making @new_person available through
+	# the local variable 'person'
+	render :partial => "person", :object => @new_person
+
+If the instance variable `name` in the parent template matches the name of the partial, you can use a shortcut:
+
+	render :partial => "person"
+
+Now the value that was in `@person` in the parent template is accessible as `person` in the partial.
+
+Partials as a View of a Collection
+-----------------------------------
+
+Often it is the case that you need to display not just a single object, but a collection of objects. Rather than having to constantly nest the same partial within the same iterator code, Rails provides a syntactical shortcut using the `:collection` option:
+
+	# Renders a collection of the same partial by making each element
+	# of @winners available through the local variable "person" as it
+	# builds the complete response.
+	render :partial => "person", :collection => @winners
+
+This calls the `_person.html.erb` partial for each person in the `@winners` collection. This also creates a local variable within the partial called `partial_counter` which contains the index of the current value. So for example:
+
+	<%= partial_counter %>) <%= person -%>
+
+Where `@winners` contains three people, produces the following output:
+
+	1) Bill
+	2) Jeff
+	3) Nick
+
+One last detail, you can place an arbitrary snippet of code in between the objects using the `:spacer_template` option.
+
+	# Renders the same collection of partials, but also renders the
+	# person_divider partial between each person partial.
+	render :partial => "person", :collection => @winners, :spacer_template => "person_divider"
diff --git a/railties/doc/guides/activerecord/basics.markdown b/railties/doc/guides/activerecord/basics.markdown
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+Active Record Basics
+====================
+
+
+
+The ActiveRecord Pattern
+------------------------
+
+Active Record (the library) conforms to the active record design pattern.  The active record pattern is a design pattern often found in applications that use relational database.  The name comes from by Martin Fowler's book *Patterns of Enterprise Application Architecture*, in which he describes an active record object as:
+
+> An object that wraps a row in a database table or view, encapsulates the database access, and adds domain logic on that data.
+
+So, an object that follows the active record pattern encapsulates both data and behavior; in other words, they are responsible for saving and loading to the database and also for any domain logic that acts on the data.  The data structure of the Active Record should exactly match that of the database: one field in the class for each column in the table.
+
+The Active Record class typically has methods that do the following:
+
+* Construct an instances of an Active Record class from a SQL result
+* Construct a new class instance for insertion into the table
+* Get and set column values
+* Wrap business logic where appropriate
+* Update existing objects and update the related rows in the database
+
+Mapping Your Database
+---------------------
+
+### Plural tables, singular classes ###
+
+### Schema lives in the database ###
+
+Creating Records
+----------------
+
+### Using save ###
+
+### Using create ###
+
+Retrieving Existing Rows
+------------------------
+
+### Using find ###
+
+### Using find_by_* ###
+
+Editing and Updating Rows
+-------------------------
+
+### Editing an instance
+
+### Using update_all/update_attributes ###
+
+Deleting Data
+-------------
+
+### Destroying a record ###
+
+### Deleting a record ###
\ No newline at end of file
diff --git a/railties/doc/guides/creating_plugins/basics.markdown b/railties/doc/guides/creating_plugins/basics.markdown
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+Creating Plugin Basics
+====================
+
+Pretend for a moment that you are an avid bird watcher.  Your favorite bird is the Yaffle, and you want to create a plugin that allows other developers to share in the Yaffle goodness.
+
+In this tutorial you will learn how to create a plugin that includes:
+
+Core Extensions - extending String:
+
+    # Anywhere
+    "hello".squawk # => "squawk! hello! squawk!"
+
+An `acts_as_yaffle` method for Active Record models that adds a "squawk" method:
+
+    class Hickwall < ActiveRecord::Base
+      acts_as_yaffle :yaffle_text_field => :last_sang_at
+    end
+
+    Hickwall.new.squawk("Hello World")
+
+A view helper that will print out squawking info:
+
+    squawk_info_for(@hickwall)
+
+A generator that creates a migration to add squawk columns to a model:
+
+    script/generate yaffle hickwall
+
+A custom generator command:
+
+    class YaffleGenerator < Rails::Generator::NamedBase
+      def manifest
+          m.yaffle_definition
+        end
+      end
+    end
+
+A custom route method:
+
+    ActionController::Routing::Routes.draw do |map|
+      map.yaffles
+    end
+
+In addition you'll learn how to:
+
+* test your plugins
+* work with init.rb, how to store model, views, controllers, helpers and even other plugins in your plugins
+* create documentation for your plugin.
+* write custom rake tasks in your plugin
+
+Create the basic app
+---------------------
+
+In this tutorial we will create a basic rails application with 1 resource: bird.  Start out by building the basic rails app:
+
+> The following instructions will work for sqlite3.  For more detailed instructions on how to create a rails app for other databases see the API docs.
+
+    rails plugin_demo
+    cd plugin_demo
+    script/generate scaffold bird name:string
+    rake db:migrate
+    script/server
+
+Then navigate to [http://localhost:3000/birds](http://localhost:3000/birds).  Make sure you have a functioning rails app before continuing.
+
+Create the plugin
+-----------------------
+
+The built-in Rails plugin generator stubs out a new plugin. Pass the plugin name, either CamelCased or under_scored, as an argument. Pass --with-generator to add an example generator also.
+
+This creates a plugin in vendor/plugins including an init.rb and README as well as standard lib, task, and test directories.
+
+Examples:
+
+    ./script/generate plugin BrowserFilters
+    ./script/generate plugin BrowserFilters --with-generator
+
+Later in the plugin we will create a generator, so go ahead and add the --with-generator option now:
+
+    script/generate plugin yaffle --with-generator
+
+You should see the following output:
+
+    create  vendor/plugins/yaffle/lib
+    create  vendor/plugins/yaffle/tasks
+    create  vendor/plugins/yaffle/test
+    create  vendor/plugins/yaffle/README
+    create  vendor/plugins/yaffle/MIT-LICENSE
+    create  vendor/plugins/yaffle/Rakefile
+    create  vendor/plugins/yaffle/init.rb
+    create  vendor/plugins/yaffle/install.rb
+    create  vendor/plugins/yaffle/uninstall.rb
+    create  vendor/plugins/yaffle/lib/yaffle.rb
+    create  vendor/plugins/yaffle/tasks/yaffle_tasks.rake
+    create  vendor/plugins/yaffle/test/core_ext_test.rb
+    create  vendor/plugins/yaffle/generators
+    create  vendor/plugins/yaffle/generators/yaffle
+    create  vendor/plugins/yaffle/generators/yaffle/templates
+    create  vendor/plugins/yaffle/generators/yaffle/yaffle_generator.rb
+    create  vendor/plugins/yaffle/generators/yaffle/USAGE
+
+For this plugin you won't need the file vendor/plugins/yaffle/lib/yaffle.rb so you can delete that.
+
+    rm vendor/plugins/yaffle/lib/yaffle.rb
+
+> Editor's note:  many plugin authors prefer to keep this file, and add all of the require statements in it.  That way, they only line in init.rb would be `require "yaffle"`
+> If you are developing a plugin that has a lot of files in the lib directory, you may want to create a subdirectory like lib/yaffle and store your files in there.  That way your init.rb file stays clean
+
+Setup the plugin for testing
+------------------------
+
+Testing plugins that use the entire Rails stack can be complex, and the generator doesn't offer any help.  In this tutorial you will learn how to test your plugin against multiple different adapters using ActiveRecord.  This tutorial will not cover how to use fixtures in plugin tests.
+
+To setup your plugin to allow for easy testing you'll need to add 3 files:
+
+* A database.yml file with all of your connection strings
+* A schema.rb file with your table definitions
+* A test helper that sets up the database before your tests
+
+For this plugin you'll need 2 tables/models, Hickwalls and Wickwalls, so add the following files:
+
+    # File: vendor/plugins/yaffle/test/database.yml
+
+    sqlite:
+      :adapter: sqlite
+      :dbfile: yaffle_plugin.sqlite.db
+    sqlite3:
+      :adapter: sqlite3
+      :dbfile: yaffle_plugin.sqlite3.db
+    postgresql:
+      :adapter: postgresql
+      :username: postgres
+      :password: postgres
+      :database: yaffle_plugin_test
+      :min_messages: ERROR
+    mysql:
+      :adapter: mysql
+      :host: localhost
+      :username: rails
+      :password:
+      :database: yaffle_plugin_test
+
+    # File: vendor/plugins/yaffle/test/test_helper.rb
+
+    ActiveRecord::Schema.define(:version => 0) do
+      create_table :hickwalls, :force => true do |t|
+        t.string :name
+        t.string :last_squawk
+        t.datetime :last_squawked_at
+      end
+      create_table :wickwalls, :force => true do |t|
+        t.string :name
+        t.string :last_tweet
+        t.datetime :last_tweeted_at
+      end
+    end
+
+    # File: vendor/plugins/yaffle/test/test_helper.rb
+
+    ENV['RAILS_ENV'] = 'test'
+    ENV['RAILS_ROOT'] ||= File.dirname(__FILE__) + '/../../../..'
+
+    require 'test/unit'
+    require File.expand_path(File.join(ENV['RAILS_ROOT'], 'config/environment.rb'))
+
+    config = YAML::load(IO.read(File.dirname(__FILE__) + '/database.yml'))
+    ActiveRecord::Base.logger = Logger.new(File.dirname(__FILE__) + "/debug.log")
+
+    db_adapter = ENV['DB']
+
+    # no db passed, try one of these fine config-free DBs before bombing.
+    db_adapter ||=
+      begin
+        require 'rubygems'
+        require 'sqlite'
+        'sqlite'
+      rescue MissingSourceFile
+        begin
+          require 'sqlite3'
+          'sqlite3'
+        rescue MissingSourceFile
+        end
+      end
+
+    if db_adapter.nil?
+      raise "No DB Adapter selected. Pass the DB= option to pick one, or install Sqlite or Sqlite3."
+    end
+
+    ActiveRecord::Base.establish_connection(config[db_adapter])
+
+    load(File.dirname(__FILE__) + "/schema.rb")
+
+    require File.dirname(__FILE__) + '/../init.rb'
+
+    class Hickwall < ActiveRecord::Base
+      acts_as_yaffle
+    end
+
+    class Wickwall < ActiveRecord::Base
+      acts_as_yaffle :yaffle_text_field => :last_tweet, :yaffle_date_field => :last_tweeted_at
+    end
+
+Add a `to_squawk` method to String
+-----------------------
+
+To update a core class you will have to:
+
+* Write tests for the desired functionality
+* Create a file for the code you wish to use
+* Require that file from your init.rb
+
+Most plugins store their code classes in the plugin's lib directory.  When you add a file to the lib directory, you must also require that file from init.rb.  The file you are going to add for this tutorial is `lib/core_ext.rb`
+
+First, you need to write the tests.  Testing plugins is very similar to testing rails apps.  The generated test file should look something like this:
+
+    # File: vendor/plugins/yaffle/test/core_ext_test.rb
+
+    require 'test/unit'
+
+    class CoreExtTest < Test::Unit::TestCase
+      # Replace this with your real tests.
+      def test_this_plugin
+        flunk
+      end
+    end
+
+Start off by removing the default test, and adding a require statement for your test helper.
+
+    # File: vendor/plugins/yaffle/test/core_ext_test.rb
+
+    require 'test/unit'
+    require File.dirname(__FILE__) + '/test_helper.rb'
+
+    class CoreExtTest < Test::Unit::TestCase
+    end
+
+Navigate to your plugin directory and run `rake test`
+
+    cd vendor/plugins/yaffle
+    rake test
+
+Your test should fail with `no such file to load -- ./test/../lib/core_ext.rb (LoadError)` because we haven't created any file yet.  Create the file `lib/core_ext.rb` and re-run the tests.  You should see a different error message:
+
+    1.) Failure ...
+    No tests were specified
+
+Great - now you are ready to start development.  The first thing we'll do is to add a method to String called `to_squawk` which will prefix the string with the word "squawk! ".  The test will look something like this:
+
+    # File: vendor/plugins/yaffle/init.rb
+
+    class CoreExtTest < Test::Unit::TestCase
+      def test_string_should_respond_to_squawk
+        assert_equal true, "".respond_to?(:to_squawk)
+      end
+      def test_string_prepend_empty_strings_with_the_word_squawk
+        assert_equal "squawk!", "".to_squawk
+      end
+      def test_string_prepend_non_empty_strings_with_the_word_squawk
+        assert_equal "squawk! Hello World", "Hello World".to_squawk
+      end
+    end
+
+    # File: vendor/plugins/yaffle/init.rb
+
+    require "core_ext"
+
+    # File: vendor/plugins/yaffle/lib/core_ext.rb
+
+    String.class_eval do
+      def to_squawk
+        "squawk! #{self}".strip
+      end
+    end
+
+When monkey-patching existing classes it's often better to use `class_eval` instead of opening the class directly.
+
+To test that your method does what it says it does, run the unit tests.  To test this manually, fire up a console and start squawking:
+
+    script/console
+    >> "Hello World".to_squawk
+    => "squawk! Hello World"
+
+If that worked, congratulations!  You just created your first test-driven plugin that extends a core ruby class.
+
+Add an `acts_as_yaffle` method to ActiveRecord
+-----------------------
+
+A common pattern in plugins is to add a method called `acts_as_something` to models.  In this case, you want to write a method called `acts_as_yaffle` that adds a squawk method to your models.
+
+To keep things clean, create a new test file called `acts_as_yaffle_test.rb` in your plugin's test directory and require your test helper.
+
+    # File: vendor/plugins/yaffle/test/acts_as_yaffle_test.rb
+
+    require File.dirname(__FILE__) + '/test_helper.rb'
+
+    class Hickwall < ActiveRecord::Base
+      acts_as_yaffle
+    end
+
+    class ActsAsYaffleTest < Test::Unit::TestCase
+    end
+
+    # File: vendor/plugins/lib/acts_as_yaffle.rb
+
+    module Yaffle
+    end
+
+One of the most common plugin patterns for `acts_as_yaffle` plugins is to structure your file like so:
+
+    module Yaffle
+      def self.included(base)
+        base.send :extend, ClassMethods
+      end
+
+      module ClassMethods
+        # any method placed here will apply to classes, like Hickwall
+        def acts_as_something
+          send :include, InstanceMethods
+        end
+      end
+
+      module InstanceMethods
+        # any method placed here will apply to instaces, like @hickwall
+      end
+    end
+
+With structure you can easily separate the methods that will be used for the class (like `Hickwall.some_method`) and the instance (like `@hickwell.some_method`).
+
+Let's add class method named `acts_as_yaffle` - testing it out first.  You already defined the ActiveRecord models in your test helper, so if you run tests now they will fail.
+
+Back in your `acts_as_yaffle` file, update ClassMethods like so:
+
+    module ClassMethods
+      def acts_as_yaffle(options = {})
+        send :include, InstanceMethods
+      end
+    end
+
+Now that test should pass.  Since your plugin is going to work with field names, you need to allow people to define the field names, in case there is a naming conflict.  You can write a few simple tests for this:
+
+    # File: vendor/plugins/yaffle/test/acts_as_yaffle_test.rb
+
+    require File.dirname(__FILE__) + '/test_helper.rb'
+
+    class ActsAsYaffleTest < Test::Unit::TestCase
+      def test_a_hickwalls_yaffle_text_field_should_be_last_squawk
+        assert_equal "last_squawk", Hickwall.yaffle_text_field
+      end
+      def test_a_hickwalls_yaffle_date_field_should_be_last_squawked_at
+        assert_equal "last_squawked_at", Hickwall.yaffle_date_field
+      end
+      def test_a_wickwalls_yaffle_text_field_should_be_last_tweet
+        assert_equal "last_tweet", Wickwall.yaffle_text_field
+      end
+      def test_a_wickwalls_yaffle_date_field_should_be_last_tweeted_at
+        assert_equal "last_tweeted_at", Wickwall.yaffle_date_field
+      end
+    end
+
+To make these tests pass, you could modify your `acts_as_yaffle` file like so:
+
+    # File: vendor/plugins/yaffle/lib/acts_as_yaffle.rb
+
+    module Yaffle
+      def self.included(base)
+        base.send :extend, ClassMethods
+      end
+
+      module ClassMethods
+        def acts_as_yaffle(options = {})
+          cattr_accessor :yaffle_text_field, :yaffle_date_field
+          self.yaffle_text_field = (options[:yaffle_text_field] || :last_squawk).to_s
+          self.yaffle_date_field = (options[:yaffle_date_field] || :last_squawked_at).to_s
+          send :include, InstanceMethods
+        end
+      end
+
+      module InstanceMethods
+      end
+    end
+
+Now you can add tests for the instance methods, and the instance method itself:
+
+    # File: vendor/plugins/yaffle/test/acts_as_yaffle_test.rb
+
+    require File.dirname(__FILE__) + '/test_helper.rb'
+
+    class ActsAsYaffleTest < Test::Unit::TestCase
+
+      def test_a_hickwalls_yaffle_text_field_should_be_last_squawk
+        assert_equal "last_squawk", Hickwall.yaffle_text_field
+      end
+      def test_a_hickwalls_yaffle_date_field_should_be_last_squawked_at
+        assert_equal "last_squawked_at", Hickwall.yaffle_date_field
+      end
+
+      def test_a_wickwalls_yaffle_text_field_should_be_last_squawk
+        assert_equal "last_tweet", Wickwall.yaffle_text_field
+      end
+      def test_a_wickwalls_yaffle_date_field_should_be_last_squawked_at
+        assert_equal "last_tweeted_at", Wickwall.yaffle_date_field
+      end
+
+      def test_hickwalls_squawk_should_populate_last_squawk
+        hickwall = Hickwall.new
+        hickwall.squawk("Hello World")
+        assert_equal "squawk! Hello World", hickwall.last_squawk
+      end
+      def test_hickwalls_squawk_should_populate_last_squawked_at
+        hickwall = Hickwall.new
+        hickwall.squawk("Hello World")
+        assert_equal Date.today, hickwall.last_squawked_at
+      end
+
+      def test_wickwalls_squawk_should_populate_last_tweet
+        wickwall = Wickwall.new
+        wickwall.squawk("Hello World")
+        assert_equal "squawk! Hello World", wickwall.last_tweet
+      end
+      def test_wickwalls_squawk_should_populate_last_tweeted_at
+        wickwall = Wickwall.new
+        wickwall.squawk("Hello World")
+        assert_equal Date.today, wickwall.last_tweeted_at
+      end
+    end
+
+    # File: vendor/plugins/yaffle/lib/acts_as_yaffle.rb
+
+    module Yaffle
+      def self.included(base)
+        base.send :extend, ClassMethods
+      end
+
+      module ClassMethods
+        def acts_as_yaffle(options = {})
+          cattr_accessor :yaffle_text_field, :yaffle_date_field
+          self.yaffle_text_field = (options[:yaffle_text_field] || :last_squawk).to_s
+          self.yaffle_date_field = (options[:yaffle_date_field] || :last_squawked_at).to_s
+          send :include, InstanceMethods
+        end
+      end
+
+      module InstanceMethods
+        def squawk(string)
+          write_attribute(self.class.yaffle_text_field, string.to_squawk)
+          write_attribute(self.class.yaffle_date_field, Date.today)
+        end
+      end
+    end
+
+Note the use of write_attribute to write to the field in model.
+
+Create a view helper
+-----------------------
+
+Creating a view helper is a 3-step process:
+
+* Add an appropriately named file to the lib directory
+* Require the file and hooks in init.rb
+* Write the tests
+
+First, create the test to define the functionality you want:
+
+    # File: vendor/plugins/yaffle/test/view_helpers_test.rb
+
+    require File.dirname(__FILE__) + '/test_helper.rb'
+    include YaffleViewHelper
+
+    class ViewHelpersTest < Test::Unit::TestCase
+      def test_squawk_info_for_should_return_the_text_and_date
+        time = Time.now
+        hickwall = Hickwall.new
+        hickwall.last_squawk = "Hello World"
+        hickwall.last_squawked_at = time
+        assert_equal "Hello World, #{time.to_s}", squawk_info_for(hickwall)
+      end
+    end
+
+Then add the following statements to init.rb:
+
+    # File: vendor/plugins/yaffle/init.rb
+
+    require "view_helpers"
+    ActionView::Base.send :include, YaffleViewHelper
+
+Then add the view helpers file and
+
+    # File: vendor/plugins/yaffle/lib/view_helpers.rb
+
+    module YaffleViewHelper
+      def squawk_info_for(yaffle)
+        returning "" do |result|
+          result << yaffle.read_attribute(yaffle.class.yaffle_text_field)
+          result << ", "
+          result << yaffle.read_attribute(yaffle.class.yaffle_date_field).to_s
+        end
+      end
+    end
+
+You can also test this in script/console by using the "helper" method:
+
+    script/console
+    >> helper.squawk_info_for(@some_yaffle_instance)
+
+Create a migration generator
+-----------------------
+
+When you created the plugin above, you specified the --with-generator option, so you already have the generator stubs in your plugin.
+
+We'll be relying on the built-in rails generate template for this tutorial.  Going into the details of generators is beyond the scope of this tutorial.
+
+Type:
+
+    script/generate
+
+You should see the line:
+
+    Plugins (vendor/plugins): yaffle
+
+When you run `script/generate yaffle` you should see the contents of your USAGE file.  For this plugin, the USAGE file looks like this:
+
+    Description:
+        Creates a migration that adds yaffle squawk fields to the given model
+
+    Example:
+        ./script/generate yaffle hickwall
+
+        This will create:
+            db/migrate/TIMESTAMP_add_yaffle_fields_to_hickwall
+
+Now you can add code to your generator:
+
+    # File: vendor/plugins/yaffle/generators/yaffle/yaffle_generator.rb
+
+    class YaffleGenerator < Rails::Generator::NamedBase
+      def manifest
+        record do |m|
+          m.migration_template 'migration:migration.rb', "db/migrate", {:assigns => yaffle_local_assigns,
+            :migration_file_name => "add_yaffle_fields_to_#{custom_file_name}"
+          }
+        end
+      end
+
+      private
+        def custom_file_name
+          custom_name = class_name.underscore.downcase
+          custom_name = custom_name.pluralize if ActiveRecord::Base.pluralize_table_names
+        end
+
+        def yaffle_local_assigns
+          returning(assigns = {}) do
+            assigns[:migration_action] = "add"
+            assigns[:class_name] = "add_yaffle_fields_to_#{custom_file_name}"
+            assigns[:table_name] = custom_file_name
+            assigns[:attributes] = [Rails::Generator::GeneratedAttribute.new("last_squawk", "string")]
+            assigns[:attributes] << Rails::Generator::GeneratedAttribute.new("last_squawked_at", "datetime")
+          end
+        end
+    end
+
+Note that you need to be aware of whether or not table names are pluralized.
+
+This does a few things:
+
+* Reuses the built in rails migration_template method
+* Reuses the built-in rails migration template
+
+When you run the generator like
+
+    script/generate yaffle bird
+
+You will see a new file:
+
+    # File: db/migrate/20080529225649_add_yaffle_fields_to_birds.rb
+
+    class AddYaffleFieldsToBirds < ActiveRecord::Migration
+      def self.up
+        add_column :birds, :last_squawk, :string
+        add_column :birds, :last_squawked_at, :datetime
+      end
+
+      def self.down
+        remove_column :birds, :last_squawked_at
+        remove_column :birds, :last_squawk
+      end
+    end
+
+Add a custom generator command
+------------------------
+
+You may have noticed above that you can used one of the built-in rails migration commands `m.migration_template`.  You can create your own commands for these, using the following steps:
+
+1. Add the require and hook statements to init.rb
+2. Create the commands - creating 3 sets, Create, Destroy, List
+3. Add the method to your generator
+
+Working with the internals of generators is beyond the scope of this tutorial, but here is a basic example:
+
+    # File: vendor/plugins/yaffle/init.rb
+
+    require "commands"
+    Rails::Generator::Commands::Create.send   :include,  Yaffle::Generator::Commands::Create
+    Rails::Generator::Commands::Destroy.send  :include,  Yaffle::Generator::Commands::Destroy
+    Rails::Generator::Commands::List.send     :include,  Yaffle::Generator::Commands::List
+
+    # File: vendor/plugins/yaffle/lib/commands.rb
+
+    require 'rails_generator'
+    require 'rails_generator/commands'
+
+    module Yaffle #:nodoc:
+      module Generator #:nodoc:
+        module Commands #:nodoc:
+          module Create
+            def yaffle_definition
+              file("definition.txt", "definition.txt")
+            end
+          end
+
+          module Destroy
+            def yaffle_definition
+              file("definition.txt", "definition.txt")
+            end
+          end
+
+          module List
+            def yaffle_definition
+              file("definition.txt", "definition.txt")
+            end
+          end
+        end
+      end
+    end
+
+    # File: vendor/plugins/yaffle/generators/yaffle/templates/definition.txt
+
+    Yaffle is a bird
+
+    # File: vendor/plugins/yaffle/generators/yaffle/yaffle_generator.rb
+
+    class YaffleGenerator < Rails::Generator::NamedBase
+      def manifest
+          m.yaffle_definition
+        end
+      end
+    end
+
+This example just uses the built-in "file" method, but you could do anything that ruby allows.
+
+Add a Custom Route
+------------------------
+
+Testing routes in plugins can be complex, especially if the controllers are also in the plugin itself.  Jamis Buck showed a great example of this in [http://weblog.jamisbuck.org/2006/10/26/monkey-patching-rails-extending-routes-2](http://weblog.jamisbuck.org/2006/10/26/monkey-patching-rails-extending-routes-2)
+
+    # File: vendor/plugins/yaffle/test/routing_test.rb
+
+    require "#{File.dirname(__FILE__)}/test_helper"
+
+    class RoutingTest < Test::Unit::TestCase
+
+      def setup
+        ActionController::Routing::Routes.draw do |map|
+          map.yaffles
+        end
+      end
+
+      def test_yaffles_route
+        assert_recognition :get, "/yaffles", :controller => "yaffles_controller", :action => "index"
+      end
+
+      private
+
+        # yes, I know about assert_recognizes, but it has proven problematic to
+        # use in these tests, since it uses RouteSet#recognize (which actually
+        # tries to instantiate the controller) and because it uses an awkward
+        # parameter order.
+        def assert_recognition(method, path, options)
+          result = ActionController::Routing::Routes.recognize_path(path, :method => method)
+          assert_equal options, result
+        end
+    end
+
+    # File: vendor/plugins/yaffle/init.rb
+
+    require "routing"
+    ActionController::Routing::RouteSet::Mapper.send :include, Yaffle::Routing::MapperExtensions
+
+    # File: vendor/plugins/yaffle/lib/routing.rb
+
+    module Yaffle #:nodoc:
+      module Routing #:nodoc:
+        module MapperExtensions
+          def yaffles
+            @set.add_route("/yaffles", {:controller => "yaffles_controller", :action => "index"})
+          end
+        end
+      end
+    end
+
+    # File: config/routes.rb
+
+    ActionController::Routing::Routes.draw do |map|
+      ...
+      map.yaffles
+    end
+
+You can also see if your routes work by running `rake routes` from your app directory.
+
+Generate RDoc Documentation
+-----------------------
+
+Once your plugin is stable, the tests pass on all database and you are ready to deploy do everyone else a favor and document it!  Luckily, writing documentation for your plugin is easy.
+
+The first step is to update the README file with detailed information about how to use your plugin.  A few key things to include are:
+
+* Your name
+* How to install
+* How to add the functionality to the app (several examples of common use cases)
+* Warning, gotchas or tips that might help save users time
+
+Once your README is solid, go through and add rdoc comments to all of the methods that developers will use.
+
+Before you generate your documentation, be sure to go through and add nodoc comments to those modules and methods that are not important to your users.
+
+Once your comments are good to go, navigate to your plugin directory and run
+
+    rake rdoc
+
+Work with init.rb
+------------------------
+
+The plugin initializer script init.rb is invoked via `eval` (not require) so it has slightly different behavior.
+
+If you reopen any classes in init.rb itself your changes will potentially be made to the wrong module.  There are 2 ways around this:
+
+The first way is to explicitly define the top-level module space for all modules and classes, like ::Hash
+
+    # File: vendor/plugins/yaffle/init.rb
+
+    class ::Hash
+      def is_a_special_hash?
+        true
+      end
+    end
+
+OR you can use `module_eval` or `class_eval`
+
+    # File: vendor/plugins/yaffle/init.rb
+
+    Hash.class_eval do
+      def is_a_special_hash?
+        true
+      end
+    end
+
+Store models, views, helpers, and controllers in your plugins
+------------------------
+
+You can easily store models, views, helpers and controllers in plugins.  Just create a folder for each in the lib folder, add them to the load path and remove them from the load once path:
+
+    # File: vendor/plugins/yaffle/init.rb
+
+    %w{ models controllers helpers }.each do |dir|
+      path = File.join(directory, 'lib', dir)
+      $LOAD_PATH << path
+      Dependencies.load_paths << path
+      Dependencies.load_once_paths.delete(path)
+    end
+
+Adding directories to the load path makes them appear just like files in the the main app directory - except that they are only loaded once, so you have to restart the web server to see the changes in the browser.
+
+Adding directories to the load once paths allow those changes to picked up as soon as you save the file - without having to restart the web server.
+
+Write custom rake tasks in your plugin
+-------------------------
+
+When you created the plugin with the built-in rails generator, it generated a rake file for you in `vendor/plugins/yaffle/tasks/yaffle.rake`.  Any rake task you add here will be available to the app.
+
+Many plugin authors put all of their rake tasks into a common namespace that is the same as the plugin, like so:
+
+    # File: vendor/plugins/yaffle/tasks/yaffle.rake
+
+    namespace :yaffle do
+      desc "Prints out the word 'Yaffle'"
+      task :squawk => :environment do
+        puts "squawk!"
+      end
+    end
+
+When you run `rake -T` from your plugin you will see
+
+  yaffle:squawk "Prints out..."
+
+You can add as many files as you want in the tasks directory, and if they end in .rake Rails will pick them up.
+
+Store plugins in alternate locations
+-------------------------
+
+You can store plugins wherever you want - you just have to add those plugins to the plugins path in environment.rb
+
+Since the plugin is only loaded after the plugin paths are defined, you can't redefine this in your plugins - but it may be good to now.
+
+You can even store plugins inside of other plugins for complete plugin madness!
+
+    config.plugin_paths << File.join(RAILS_ROOT,"vendor","plugins","yaffle","lib","plugins")
+
+Create your own Plugin Loaders and Plugin Locators
+------------------------
+
+If the built-in plugin behavior is inadequate, you can change almost every aspect of the location and loading process.  You can write your own plugin locators and plugin loaders, but that's beyond the scope of this tutorial.
+
+Use Custom Plugin Generators
+------------------------
+
+If you are an RSpec fan, you can install the `rspec_plugin_generator`, which will generate the spec folder and database for you.
+
+[http://github.com/pat-maddox/rspec-plugin-generator/tree/master](http://github.com/pat-maddox/rspec-plugin-generator/tree/master)
+
+References
+------------------------
+
+* [http://nubyonrails.com/articles/the-complete-guide-to-rails-plugins-part-i](http://nubyonrails.com/articles/the-complete-guide-to-rails-plugins-part-i)
+* [http://nubyonrails.com/articles/2006/05/09/the-complete-guide-to-rails-plugins-part-ii](http://nubyonrails.com/articles/2006/05/09/the-complete-guide-to-rails-plugins-part-ii)
+* [http://github.com/technoweenie/attachment_fu/tree/master](http://github.com/technoweenie/attachment_fu/tree/master)
+* [http://daddy.platte.name/2007/05/rails-plugins-keep-initrb-thin.html](http://daddy.platte.name/2007/05/rails-plugins-keep-initrb-thin.html)
+
+Appendices
+------------------------
+
+The final plugin should have a directory structure that looks something like this:
+
+    |-- MIT-LICENSE
+    |-- README
+    |-- Rakefile
+    |-- generators
+    |   `-- yaffle
+    |       |-- USAGE
+    |       |-- templates
+    |       |   `-- definition.txt
+    |       `-- yaffle_generator.rb
+    |-- init.rb
+    |-- install.rb
+    |-- lib
+    |   |-- acts_as_yaffle.rb
+    |   |-- commands.rb
+    |   |-- core_ext.rb
+    |   |-- routing.rb
+    |   `-- view_helpers.rb
+    |-- tasks
+    |   `-- yaffle_tasks.rake
+    |-- test
+    |   |-- acts_as_yaffle_test.rb
+    |   |-- core_ext_test.rb
+    |   |-- database.yml
+    |   |-- debug.log
+    |   |-- routing_test.rb
+    |   |-- schema.rb
+    |   |-- test_helper.rb
+    |   `-- view_helpers_test.rb
+    |-- uninstall.rb
+    `-- yaffle_plugin.sqlite3.db