Negativland fan here, and I suspect hope there might be a small clutch of other MSTies who are as well.
The best way I can describe their output is that they ingest massive amounts of audio, from lots of varying sources, then mince it and spit it out into a totally new and recontextualized thing to make a statement or tell a story (albeit a bizarre story).
The thing most people know from Negativland is “some U2 cover where Casey Kasem flips out” (Col. Sanders and Orson Welles got similar treatments) but no territory is safe from their tape reels. One song teaches us the origins of the U.S. national anthem while another imagines Disney’s Great Moments with Mr. Lincoln going in a very different direction. They have an entire album dedicated on the topic of cola war advertising. And when they aren’t working on an album, they’re on the radio (still, although in a more limited capacity these days) playing live with listener participation.