This is the one I used for random sigs a while ago: http://endlessparadigm.com/forum/showthread.php?tid=638
(just edited it to add in something which I feel should be there)

The EP one is different, as it selects pictures based on time.  Also, it's "internal" - ie doesn't link to a PHP script (and allows caching and runs faster).


If you don't have your own server, then you can't use PHP scripts.  A random Javascript image generator might be better - but then, you'd have to be able to put your own Javascript code in.