According to iTunes, it's "Your Kisses Are Wasted on Me," by the Pipettes. Last.fm, which has data from before I got this computer, says that it's a tie between "The Cap'm" and "Withered Hope," both by They Might Be Giants. That doesn't include anything I listen to while not on the computer, though.
Okay, I think I'll go to bed now. I'll probably put up an Oz post when I wake up. Happy Labor Day!