http://www.nintendo.com/gamesites/wii/fluidity/
This is a new WiiWare game, and it's just as innovative as World of Goo for instance. You are basically a pool of water, and you travel around the world of a book. Apparently the book has been stained with inkblots, so you have to clean it up by completing tasks to get Rainbow Drops, which give the book some sort of energy haha. Anyway, this physics engine for this game is really awesome, and the tasks and puzzles are really fun to solve. It's one of the best WiiWare games out right now.