You know how phpinfo() generates two images, the php and the zend logos? Well if you look at the URL for those it will be like:
phpinfo.php?=PHPE9568F34-D428-11d2-A769-00AA001ACF42
I don't know if the numbers will be exactly the same each time, but numbers of the two images should be in a sequence. If you request the url with the next number in the sequence you will get a funny pic 🙂
Looks like there is only the one, if you find another one let us know.
-nick