Dunno if this one has been said yet, but here goes.
You are trapped in a room with two doors; one of which leads to heaven and the other leads to hell. There are also two birds in the room; one of which always lies and the other always tells the truth. You don't know which bird is which and you don't know which door is which. You may ask one question to one bird, and you may only choose one door.
How do you decide which door leads to heaven?
(atheism or a random guess are not acceptable answers :3 )
