As a firm agnostic, and as I get very annoyed at atheists who want me to convert to their anti-religious camp, I suppose I should defend myself.
I've heard Russel's Teapot before, and to me, it's a silly comparison.
There are unknown things in this universe. Things that science cannot explain. Things that science will not even bother to explain, some of them. I'm not particularly one for supernatural trickery, but there certainly are things that science is scratching its collective head at. This is not to say I firmly believe that ghosts exist: in fact, I rather doubt it. But there have been some interesting occurrences, and there is little to prove that they are for certain completely unreal. Paranormal isn't my field; feel free to look into this on your own.
Furthermore, there is one, quite simple thing here. If God, or anything supernatural exists, it is outside of the world. And thus, we are dealing with not the nature of the world as we can see it, but the nature of an unimaginable ALL. It deals with the questions of what time is, how the universe came to be, and what might exist outside of the whole. There are interesting speculations on it, and in my opinion, there is no good reason that there cannot be more out there, something science simply cannot deal with. In fact, there are good reasons for something to be out there: it would explain much that science has not...
Now, this is all rather silly to worry about in our lifetime, so I don't actually participate in the whole religion versus science debate. I remain an agnostic, and I will continue to get irked at people who try to use scientific arguments against God when God is outside the scope of current science.