Nice topic. I consider myself Buddhist, in part for cultural reasons, and not just because I relate to Buddhist ideas about the nature of reality.
I am also an atheist - and one of the beauties of Zen Buddhism is that it is a spiritual path and philosophy that does not require what I consider to be superstitious beliefs in "god", or a desire for reward in some afterlife.
Buddhism is also inherently friendlier to sexual minorities - unlike the monotheisms, which are the origin of some of the most homophobic ideologies in history.