(I can only confirm this in the U.S.) There is a small deal that is going on Xbox Live. If you buy all of the Summer arcade games from Xbox Live you will be given 800 Microsoft Points. Though, this isn't something that I would do just for the points as the games combined would cost more the then a new retail 360 game. The games you would have to buy are Shadow Complex: 1200MSP, Splosion Man: 800MSP, Marvel vs. Capcom 2: 1200MSP, Turtles In Time RS: 800MSP, and Trials HD: 1200MSP. This offer is valid until 11:59PM EST August 31.
Yeah, I know. If you were planning on getting all of those games its not a bad deal, but definitely not worth buying all of the game just to get the 800MSP.