8. Amy Winehouse, 'Rehab'
The humor in Winehouse's 2006 salvo is darker now, given subsequent crack binges and other misbehavior. But "Rehab" still sums up the London diva's greatness: Sonically letter-perfect retro soul with producer Mark Ronson's 21st-century beat-muscle and cheekiness. "He's trying to make me go to rehab," she sings, "I won't go, go, go." You go, girl.