I'm agnostic leaning more toward atheist, but I don't have all the answers and think there's at least the possibility there could be a god out there.
My reasoning is this, through various events in my life I have found it hard to believe that God, I was brought up Catholic, would allow these things to happen to good people. As I got older and continued to take a hard look at the world I live in I find it unlikely God exists. So I suppose I can sum it up with a good helping of cynicism from Saving Private Ryan when Tom Hanks says something to the effect of "I took a good hard look around and realized God left this place a long time ago." I also prefer the thinking behind scientific theories and the like as opposed to it was "God's will" or something to that effect.
However, I have absolutely nothing against religious people and completely respect their decision to be religious. It's even better when the religious people can respect my point of view.