As I mentioned earlier, Thanksgiving's coming up and that means Christmas Shopping Season is coming up. I expect to be posting various stories along these same lines in the upcoming week and a half. Anyway, this time around it's Geek Fever Games. Though the sale they're having is a bit more interactive than most.
During the course of the sale, the more people that order Mars vs. Earth, the more the discounted price will be. So if everyone on the Earth gets together and orders it, it just might be free! (Note: That's speculation on my part, and I doubt it will actually be how it works. But you never know until they post all the details).