You can debate a great deal of things.  Some things you can debate because they are very far away, very small, or just plain beyond our instruments as they currently are.  However theists have said that it's impossible to debate God because He or she or It is ultimately beyond anything we can and will ever know... and yet the elephant in the room seems to be ignored by almost everyone I've ever listened to.  This God, they so claim, is supposed to be a sentient being.  God isn't some theoretical particle or some far off planet.  God is supposed to be a being that is all powerful, and unlike these inanimate theoretical subjects, capuable of proving himself.

When a Theist argues to me about if there is a god or not, I simply say "God, what do you think about that?" and wait a few moments in silence waiting for a reply "Sorry, I guess that is that".  Or if someone tells me somethings true because it was written in the bible I simply say "Tell the author that I would like to discuss that subject in person"

Also, I would very much like to see a Lawer call God to the stand, and wait for him to take a seat :3