I'll kick it off. When I went to retrieve the car from the barn in Illinois, I found a dead cat on the air cleaner. Not a freshly dead cat, but it wasn't exactly mummified yet either. It was ripe.
Then tonight, I crawled under the car to poke around. and I what looked like a mouse skull peeking out at me from the inside of the frame rail.
A little farther up, where the hole in the frame rail is, I started poking around the hole and found a nice mouse nest inside the frame. I can't believe it rotted there. Surely mouse piss should have preserved that bare metal right.