Scorpio Rising (1964)
I suppose I just want to add to everyone’s lovely examples the idea that mashups aren’t really anything new…filmically they are the spawn of montage, meaning the juxtaposition of normally alienated sound and image or image and image…classically with the Communist/Soviet montage of Eisenstein. Prior to that the idea of remixing is probably as old as tales themselves, as old as oral retelling/remixing.
The above clip is from a great gay filmmaker, Kenneth Anger. He took straight iconic imagery and pop songs and queered them as well as gave them a savage, sinister angle. He mixes in a movie version of Christ’s life, seemingly innocent comic books, various iconic images, old horror movies, and Elvis’ Devil in Disguise (taken off of the YouTube video for copyright violations). These items are juxtaposed in a way which deliberately queers the eye of the watcher.