Bar of diagnostic info for Rails. Inspired by http://rob.cogit8.org/blog/2008/Sep/19/introducing-django-debug-toolbar/
Expect this to need extending to be useful for you. Patches accepted, forking encouraged.
class ApplicationController < ActionController::Base
after_filter ::RailsDebugBar
end
Copyright (c) 2008 Bryce Kerley, released under the MIT license. My version: http://github.com/bkerley/railsdebugbar/tree/master