I liked the following Pascal's wager for believing in the existence of God, based on Christian philosophy. Here +1,0,-1 denotes positive, neutral and negative effects respectively.
If I don't believe in God and God exists, I go to hell (-1)
If I don't believe in God and God doesn't exist, nothing happens (0)
If I believe in God and God doesn't exist, nothing happens (0)
If I believe in God and God exists, I go to heaven (+1)
From above we see that the gains we get in believing in God is always greater than the gains obtained by not believing in God. So, it is always better to believe in God ! Of course, this argument has strengths and weakness, but it appeals me from probabilistic point of view.