Billy Bob Thornton The GREATEST BAND of All Time Is ...


... the Beatles. Duh.

BUT ... Billy Bob Thornton says if he HAD to name the greatest band of all time -- but couldn't pick the Fab 4 -- he knows exactly which group he would pick.

Hint: BBT's (second) favorite band was huuuge in the '70s ... but never scored a #1 hit on the Billboard Hot 100 list. They did have a #2 ... with the word "Man" in the title.

Second Hint: The group was founded (and named after) two brothers.

Now guess ... and then watch the video.