Video Collage

A Video Collage is a video made from clips of video and animation, juxtaposed in various ways. While video collages have existed as an art form since the 1960s, they were something of a film-school peculiarity until the explosion of video capture and editing tools and the rise of online video repositories such as YouTube made it a rather trivial matter to put one together.

Generally overlaps with the following, many of which use video collage extensively:
 * Animutation (basically a sub-trope)
 * Fan Vid
 * Stupid Statement Dance Mix (the accompanying videos are typically done this way)
 * YouTube Poop

The Other Wiki calls this a "Collage film".