Ever create Rails views that don't user the controller at all just to take advantage of an application layout?
If you have, you may have a lot of code that looks like this:

class HelpController < ApplicationController
  def index
  end

  def tutorial
  end

  def faq
  end
end

Well, there's a simple way to make this a lot cleaner...

class ApplicationController < ActionController::Base
  def self.simple_action(*actions)
    actions.each {|action| class_eval("def #{action}; end")}
  end
end

Now your controller can look like this instead...

class HelpController < ApplicationController
  simple_action :index, :tutorial, :faq
end