AVICII gets Rick Rolled - but theres some tubthumping going on aswell
https://www.youtube.com/watch?v=oT3mCybbhf0

Britney Style
https://www.youtube.com/watch?v=qvs2SO4inkA

Spice Girls take on the Black Eyed Peas
https://www.youtube.com/watch?v=LzvfwETPWHs

Let her go
https://www.youtube.com/watch?v=yDup-uTc8oI

Know any good ones?

edit - wow this is brilliant https://www.youtube.com/watch?v=2fIlT_IfTBQ