Faith Fighters, a flash-based 2D fighter by Molleindustria, is exactly what its name suggests. You pick a deity (choices include God, Muhammad, Ganesh & Jesus), you get an opponent, you fight to the death, Street Fighter-style. It's goal, according to Molleindustria, is to "push gamers to reflect on how [their] religions and sacred representations are often instrumentally used to fuel or justify conflicts between nations and people". OK! Muslim readers upset at the inclusion of a physical representation of the prophet Muhammad (ie a big no-no), there's a censored version of the game should you (or anyone else not already put off the game) still want to give it a try. I'd recommend it. The art style's got a very The Behometh (Castle Crashers) feel to it, and for a flash-based fighter it's pretty great.

Faith Fighter [Molleindustria, via Water Cooler Games]