How about an ugly fabric challenge? Those can be really fun. Get with your LQS and get however many yards of fabric you think you'll need and cut it into fat quarters. Put the fat quarters in paper bags so nobody can see it before hand and then hand them out to the challenge takers. You can add rules like having to use at least half of the fat quarter and it must be visible on the front and not just binding.
(The key to buying a truely ugly fabric is the LQS has had it on sale for more than a month at $3 or less a yard and there's still half a bolt. LOL)