Hover image on background

Hi, anybody know of a script available that can do this.. A random image link that floats on the background? example here http://decentarcade.com It's on the right side. Thanks..

 

This is the one that they used on that site in your link:
www.jtricks.com/javascript/navigation/floating.html

 

Thanks aidan, thats the one worth bookmarking, but i know a way to do it without any JavaScript

 

Thanks this script is handy Will be using it myself. is there any other scripts that you know of aswell?