Ha! Agnostic atheist. Not many of them around here, eh?
(How I define it: We cannot know for sure whether god exists (agnosticism.) We have no evidence, and, as of now, evidence is impossible to obtain. Because I don't know whether god exists, and because I have no evidence, I have no belief in god (atheism.) It's not that I believe god doesn't exist; it's that I have no belief in god. This is why I can define myself as an agnostic atheist. If you disagree with me on this, it doesn't really matter. It's just a label. My beliefs will still remain the same regardless of how I am labelled—namely that we cannot know whether god exists, that we have no evidence of god's existence, and that I have no belief in god.)
Edit: I should make clear that when I refer to god, I speak of some sort of higher power—not a Christian God, Islamic Allah, or whatever else, just a higher power. Additionally, when I say that I have no belief in god, I mean that I have an absence of belief.