I have the jeepers creepers song in my head all the time. I'm always humming it. My wife is constantly telling me to stop but I don't even realize I'm doing it.
One time a few years back myself and the guys I was working with out at a wind farm got that men at work song "I come from the land down under" burned into our brain! We were singing it 18 hours a day, another guy printed out the lyrics and everything. Try getting that out of your head!