ruby script/plugin install http://acts-as-noteable.googlecode.com/svn/trunk/acts_as_noteable/

* Make you ActiveRecord model act as noteable.

 class Model < ActiveRecord::Base
 	acts_as_noteable
 end
 

* Add a note to a model instance

 model = Model.new
 note = Comment.new
 note.body = 'Some comment'
 model.notes << note
 

* Each note references a noteable object

 model = Model.find(1)
 model.notes.get(0).noteable == model
 

There is currently no advanced documentation for this plugin.