There's ompf2 now, but it's a shadow of the former ompf.org forum for ray tracing, and it had the most amazing thread full of such glitch renderings. I'll link the new one here, but it's such an enormous loss (also the owner, a good friend, of the forum fell off the face of the earth): http://ompf2.com/viewtopic.php?t=25

In general that's yet another great thing about graphics programming: your bugs often have spectacular visual manifestations :)