MMO Calendar is a non-profit annual fund-raiser, with 100% of the proceeds going to support the St. Jude Children's Research Hospital. The calendar was put together in collaboration with game developers, and includes original artwork from some great MMOs, including World of Warcraft.
If a spiffy calendar and support for a wonderful charity weren't enough, each purchaser will be entered to win one of ten prizes for each MMO, totaling 130 possible prizes. In addition to potentially snagging one month of free WoW, you could also win free playtime for some other MMOs, a copy of Guild Wars: Platinum, or one of three beta keys.
Unfortunately, the calendars will only be on sale through November