How'd you track it down?
Please don't laugh now - it only took two search attempts! I was really surprised to actually find anything ...
Eventually the words "linux screensaver art"
did the trick in the Google picture search. But to be honest it was just plain luck.
BTW, the screensaver is really nice!
PS: I was watching this forums for quite a while, but never found the time to register. But as i found the answer to your question i finally had to. - So it did pay off for me, too!