I've been driving around a lot for work and listening to my new Chuck Ragan CD on repeat (if you haven't heard of him, look him up... Awesome folk-ish sound). So I randomly start humming his tunes while I'm sitting around. I just indulge myself whenever I get things stuck in my head. I take it as a sign that I want to hear it more, so I listen to it over and over again until I'm sick of it.