I can't prove that god exists, nor that he/she/it does not. And, as many others have said, it's impossible to prove that anything actually exists, if we take everything down to its roots. Science exists within the context of our world... change one thing early in a strain of scientific theories which build upon each other, and you render every subsequent theory untrue. Perhaps, in a scientific context of which we are not yet aware, it is quite possible for a higher power to exist. However, I'm not entirely certain that it's impossible within the current context.
I believe that nothing we see here on earth could have occurred in the absence of a higher power. I have no idea what or whom that higher power may be. I call myself a Christian because I believe in Jesus Christ as savior, but even that belief has become tenuous over the years, as I have learned more about the world. And the older I get, the more afraid I become that I've gotten it all wrong... and yet, I'm more afraid that I have it right, and that people I love will be lost in their unbelief.
I wish it were possible to prove god's existence and nature. I would be first in line to find out the truth, regardless of cost.
SD