Shoutbox

You use a a server side scripting lang to genarate the picture then you link to the script in your sig.
for mine i use php and use the GD libary to generate the picture. if you want i can teach you how to do it or if you like i could make you a script to do whatever you want just contact me on msn (darktempler@gmail.com)
also if you want random pictures showing you could use KMAS