Once upon a time, Hollywood was good at co-opting and selling youth culture. When rock 'n' roll and biker gangs came along in the 1950s, the studios came up with generational totems like "Blackboard Jungle" and "The Wild Ones." Beatlemania spawned "A Hard Days Night" and "Yellow Submarine," while the hippies flocked to films like "The Graduate" and "Easy Rider." Disco fueled "Saturday Night Fever" and hip-hop "Boyz n the Hood."