It's also discussed here but please DO NOT reference the meme that's out there regarding this phenomenon. It's a stupid meme that compares "having a song stuck in your head" to a certain invertebrate. I hate that frickin' meme. I've always used Suzanne Vega's "Tom's Diner" as a sort of mental-musical-sorbet. It works for me, but some people hate that song more than whatever's stuck, so - *shrug* Okay - Go.
Curious George: Song in Your Head? Okay Monkeys, you've got a song stuck in your head. 1) How do you suggest getting it out? 2) What song is it?