Was playing the Penguin Attack game, and thought: Why not have a driving game where you actually steer to the left or right like a steering wheel when you hold the iphone horizontally and screen facing you??? You could make it a simple 2D game like Pole Position or Super Sprint in the 8-bit days! Accelerate and Brake could either be tilting forwards and backwards, but I think that limits your view... probably better to have thumb overlays like gpsPhone and PSX4ALL.
There was this really addictive game called "F1 Race" on the classic Gameboy, the first 4-player game, and even just the time trials was really addictive... it had a Turbo you could use per lap, and used to be really competitive with my brother to get the best times, while avoiding the traffic. If this game could be uploaded to some high-score board, it could grow a big following.
Any developers able to do that?? (Or maybe even release that game already?!?!)