Joe Strummer and Mick Jones didn't just give Rancid's pair of singers an idea about sharing lead vocals: On London Calling, the Clash's mix of raw punk and reggae showed the U.S. band how to leaven rage with danceable release. All that was needed was a dash of ska seasoning—thanks to The Specials—and a bit of raw American hardcore, courtesy of Minor Threat and T.S.O.L.