Sven-Åke Johansson - Konzert für 12 Traktoren
Here's one I recently discovered: Sven-Åke Johansson's "Konzert für 12 Traktoren" (Concert for 12 Tractors). Being the Avant-Garde buff that I am, this, of course, quite fascinated me (and I do have some strange records in my collection).
If you want to check it out, this masterpiece (no pun intended, seriously) can be heard here in all its glory
Available as a DL or on Vinyl.