Plugins - ColumnComments
Add to favoritesThe ColumnComments plugin makes the necessary modifications to ActiveRecord to allow for an optional :comment in your table migrations. In addition, it includes the same feature provided by the AnnotateModels plugin (rake annotate_models), but also includes the database-stored comments in the auto-generated header.
http://blog.inquirylabs.com/2006/04/27/columncomments-rails-plugin
svn://syncid.textdriven.com/svn/opensource/column_comments/trunk
Rails' (MIT)
Model

Note that this plugin does not play well with the RedHillOnRails Core plugin.