Exquisite Corpse 56, by Josephine Meckseper, Laurie Anderson, Olaf Breuning, Nick Mauss. (Yes, that is Susan Boyle's grinning face.)
What, you don't know about this parlor game? Well, there's Wikipedia, or, from the gallery curating a selection of such pieces:
Over 200 important contemporary artists have come together to create collaborative drawings based on the 1920's surrealist parlor game "cadavre exquise". The project is meant to celebrate the theme of chance encounters, surprise and radical juxtaposition. Each artist adds to the composition, in sequence, without seeing the contribution of the previous person.