Dead, decomposed fox removed on a hot summers day from the gallops at a riding school, so the clients wouldn't see it. I was the only member of staff deemed to have the stomach for it...it was, uh, not pleasant and broke apart when I moved it.
Bag of forgotten carrots at the back of a cupboard - liquified. Just smells like vomit.
Old dried vomit. At the bottom of a wardrobe. Not me, don't ask.