Evenin' all. I have just spent about 20 minutes dicking about with this. Which, I think, gives it the official Paul Seal of Approval. The concept can be explained thus: Draw a picture, submit and get someone else's picture. More absorbing than it sounds. Some people really put effort into these things. Must be annoying when they get my scribbles in return!
Anyway. Sketchswap, it does what it says on the tin.