The Speed Gamers are doing a 72 hour marathon run of Prince of Persia and Assassin's Creed, raising money for restoration of the Gulf of Mexico. It is currently going on right now, here's the link to the live feed.
http://www.thespeedgamers.com/
I think this is an awesome thing to do.
(Also I wasn't sure if this was the right section to put it in but I figured it's alright. >.>)