The Roots "come alive" on Jimmy Fallon.

Justin Timberlake was a guest on Late Night With Jimmy Fallon, promoting his film The Social Network, when he and Fallon broke out into a rap medley. The only thing funnier than Fallon asking if the Roots know "some Sugar Hill Gang" is how Fallon and Timberlake kick it on a number of "old skool" classics. Norman Mailer's "White Negro" is far from dead. Check out the video below: