The thread is old, so some of the pictures have disappeared and you may have already seen it, but this Photoshop contest is awfully damn funny. Two warnings:
1. It runs for 50 pages or so, and I stopped at about page 25 last night as the quality was beginning to dip. Perhaps it got better from there, perhaps not. Your mileage may vary.
2. If an exposed butt is a violation for wherever you are surfing, well, there's an exposed butt in pretty much every picture.