Jimmy Fallon and Justin Timberlake Perform Epic ‘History of Rap’ Medley [VIDEO]

On 'Late Night With Jimmy Fallon,' the funnyman and guest Justin Timberlake surprised the audience with a roof-raising medley of history's greatest rap hits, from the Sugarhill Gang's 'Rapper's Delight' all the way to Jay-Z's 'New York, New York.'  Watch the clip below: