......two in two or four
    four in four or eight
    eight and eighth notes, sixteenths
    sixteenths and sixteenths, thirty------AAAAAAAARRRGGGHHH!

(Every good earworm needs an intro)

Currently I cannot get rid of "Black-Eye Peas be rappin' it RIIIIIIGGHHT NOWWWW"
At least it beats "Hey Yah." Blessedly, "It's Hard Out Here for a Pimp" has failed to hijack my conscious brain.

The US is far more dangerous earworm territory than the UK, IMHO.