mashup (māsh'ŭp') n. A combination of multiple sources of video and/or audio —which usually have no relation with each other—into a derivative work, often lampooning its component sources or another text.
This is the first song I ever heard under the description "mashup."
Here's one for the B-boomers.
Ever wonder how Kubrick's The Shining could have gone?
Here's another version of Toy Story.
And one that completely boggles me -- Must Love Jaws.
And finally -- a Titanic movie guys can get into. I give you Titanic Two: The Surface.
(Edit: After I posted this, I found one more, a work of genius. Something for my comic book geek friends. Toy Story 2 meets The Dark Knight.)