lets see if this works... Heres a graph bar I use on my site.
http://bs-linux.com/stats/loadgraph....th=25&avg=0.25
http://bs-linux.com/stats/loadgraph....th=58&avg=0.58
If this works note that both images are the same php file with different ?width settings...
ok so a .php file is ok just can't have any ?blah=blah stuff at the end... If you click the links you will see that the image changes based on my width setting. You can use the image() function to make your sig random looks like. Just do a image from jpg in your php and then randomly use one of the 2 or more images you wish from your site.
http://php.net/image for more info on this...