Made juice from pineapple skins and let it sit in my fridge sealed for a long ass time. I opened it today, expecting it to be trash, but to my surprise it was totally fine. Assuming that the yeast from the pineapple skin kicked in. Pretty damn tasty too. 10/10, would recommend, although I'd recommend actually doing this intentionally
I'm pretty big on homebrewing. Mead in the style of tepache (low alcohol, the fermentation is for carbonation) is my personal favorite.