This is a demo app written in ruby based upon the jquery ajax example:
	http://docs.jquery.com/Tutorials:Getting_Started_with_jQuery#Rate_me:_Using_Ajax

Instead of PHP, ruby and sinatra are used to do the server side operations.

See this blog post for more information:
	http://www.r-chart.com/2010/07/ajax-using-jquery-to-sinatra-and.html