The last shot of the original film is a zoom out of the cross which is left behind. In the foreground, a shepherd can be seen walking by. It was not planned that way, but the filmmakers felt that it fit the scene so well, they kept it in the film.
Judas being surprised by fighter jets screaming by was completely unexpected (they were genuine Israeli fighters on patrol) and was kept in the final cut.
One of those up for the role of Jesus was a nineteen-year old actor from New Jersey named John Travolta. Not saying it would've been good, but it certainly would've been interesting.
Ted Neeley auditioned for Judas. No, seriously.
The 2014 revived touring production was going to have John Lydon as Herod, Brandon Boyd as Judas, Michelle Williams as Mary Magadalene, and JC Chasez as Pontius Pilate, before being abruptly cancelled by the promoter. Oddly enough (or not) the promoter also happens to be the one behind Spider-Man: Turn Off the Dark. The promoter is currently being sued for breach of contract by Andrew Lloyd-Webber.