Drupal Fu is a Ruby on Rails plugin that helps with integrating Rails applications with Drupal.
You have two choices for installation. The first uses a gem (recommended):
config.gem "harukizaemon-drupal_fu", :lib => "drupal_fu", :source => "http://gems.github.com"
Or you can use the Rails plugin
$ ruby script/plugin install git://github.com/harukizaemon/drupal_fu.git
This plugin is copyright 2009 by 2009 Cogent Consulting, Pty. Ltd. and is released under the MIT license.