StarCraft 2 for $30
I don't normally endorse game sales, but StarCraft 2 is half price from now until Monday. This is my absolute favorite game from the past 2 years and I recommend it to everyone, even at full price. I love it so much I've written a whole Newbie Guide about it. If you are an RTS fan and you don't own SC2 you don't know what you're missing. If you've ever been intrigued by Starcraft 2 now is the time to pick it up.