test.rb

module RockNRole
	def self.included(base)
		base.send :extend, ClassMethods
	end

	module ClassMethods
		def has_rockin_roles
			send :include, InstanceMethods
		end
	end

	module InstanceMethods
		def rock_out
			puts "rock!"
		end
	end
end

class User
	include RockNRole
	has_rockin_roles
end

User.new.rock_out