Today marks the 70th birthday of the most prolific musician in the history of rock music, Paul McCartney. It's difficult to imagine any band taking the Beatles' spot as the undisputed greatest rock act of all time -- and although over 50 years has passed since the Beatles formed, countless acts still cover the music of the mop-topped kids from Liverpool.

Alice Cooper teamed up with guitar god Steve Vai and former Guns N' Roses bassist Duff McKagan to create an awesome cover of 'Hey, Bulldog.' The trio put their version of the Beatles classic to tape for the 2006 tribute album 'Butchering the Beatles.' On that same tribute album, Motorhead's Lemmy Kilmister teamed up with John 5 and KISS' Eric Singer for a cover of 'Back in the USSR.'

Type O Negative took the Beatles' music to a dark and gloomy place with an interesting medley of 'Day Tripper,' 'If I Needed Someone' and 'I Want You (She's So Heavy). The medley was included in the band's 1999 album, 'World Coming Down.'

Aerosmith found some common ground with the Beatles as Steven Tyler and ccompany met the 'Fab Four' halfway with a rocking version of 'Come Together.' The version was recorded in 1978 and became a monster hit of its own.

Finally there is the heavy metal version of 'Helter Skelter' by Motley Crue. 'Helter Skelter' is easily one of the hardest-hitting Beatles tracks in the band's prestigious discography, and Motley Crue turn it up just a bit louder for their version of the song.

In tribute to a true living legend, we want you to tell us which of these five Beatles covers is your personal favorite. Cast your vote in the poll below. Happy Birthday Paul! Here's to another 70 years!