Today, I wrote PHP,Jquery code for shortest URL that are bit.ly and tinyurl. I get PHP code from  http://davidwalsh.name/  and then I combine with Jquery. Bravo! It's so useful for me. Light weight and faster than their home site becuase of graphic ;). By the way, I am written this site with HTML 5 and you need to firefox 3.5 or Chrome 2