Super Meat Boy, you should go download it from XBox Live if you have the option, or on your PC if you don't, and give it a whirl. This is probably the best platformer game I've ever played that wasn't a Super Mario Bros. game. It is very fast-paced and very brutal - you will die, a lot, playing this game. And yet you will still have fun.
I'd be playing it right now, to relax from work et Krimble, but I'm too busy biting my nails waiting for Prospero Burns to make its way across the Atlantic. If I'm lucky I'll be able to scrounge a copy this weekend. Fingers crossed!