Being as this is a competition encouraging you to prototype a game in a pretty short space of time, I'd recommend you read this whitepaper, written by the guys behind the Experimental Gameplay Project at CMU. Over the course of one semester, they made something like 30 small games, each one taking no more than a week. There's some very good advice in there for anyone looking to enter Seeing Double.

wow, awesome article! i'd argue this as necessary reading for anyone studying game programming. i learned a thing or two!