What I mean by re-dub is that an original video is edited and synchronised to a different song.
In descending order...
Here we have a sped up Beatles video synchronised with Anal C*nts "Going to a Phish Concert to Beat-up Hippies for their Drugs".
A re-splicing of Immortal's videos to the Scissor Sisters "I Don't Feel Like Dancing".
The best I've seen for last:
Tommy Seebach's "Apache" to Cannibal Corpse's "Hammer Smashed Face"!