9. Guns N' Roses - 'Knockin' On Heaven's Door''
Originally written for the soundtrack to Pat Garrett and Billy The Kid, "Knockin' On Heaven's Door" gave Bob Dylan a much-needed hit after years of being written off as a washed-up Sixties relic. The song was covered by everybody from Eric Clapton to U2, but in 1990 Guns N' Roses recorded it for the Days of Thunder soundtrack and introduced it to an entirely new generation. It's been a staple of their live show ever since.