It would be quite interesting to have a content based contest. Just a bunch of sounds, music files, bitmaps and/or models. No description of what the game should be, and judged for origionality around graphics and use of sound. Modification of origionals should be minimal (IE: Its ok to render a 3D model for use in a 2D engine, or to tint the model to gain more elements from it, it shouldn't be ok to up the poly count, or re-draw any 2D art provided).

Could be like the MIT cardboard box challenge. Use as much as you can from the box (including the box) and points based from that.