My co-winner for most hypnotic game of E3 was Jon Mak's one-man-show, "Everyday Shooter." The game will be the first on PS3 to be created by a single developer. But that's not the best reason to pay attention to the project. The hook, I submit, is the music, the sound effects ... everything you hear from this game. It's all the product of Jon Mak strumming his guitar.
You might also want to check out Jon's homepage. Do note that the "ES" trailer he has there plays part of the game's soundtrack but does not demonstrate how the guitar-based sound effects actually work in the game.
Jon is wrapping the game up right now, but was able to chat with me about his goals for the project two weeks ago in Santa Monica. Look for the game on PS3's download store later this summer.