The Amazon Turk service was used to pay ten thousand anonymous people one cent to draw a small part of the hundred dollar bill (oekaki style). Then they put them all together, and are selling prints for $100 to donate to charity.
I've seen this sort of game before. It's actually a very cool idea, and the final image looks even better than the original, especially if each person used different materials/colors/whatever to make their section of the image. I don't remember what the game is called, but a lot of elementary school teachers do this with their students at least once. Or so I've heard...