My brother brought home some alcoholic fruit cocktail from a party once. I don't remember what he called it, but basically, it was fermenting fruit in a jar. It was really easy to keep it going. You would spoon some of it out and serve, and then replace that same volume with fruit cocktail out of a can, and it would take off. You could actually see the bubbles within the pieces of fruit. Pineapple worked about the best, and eventually, I got one jar going with nothing but that in it. When you bit into a piece, the carbonation would make your mouth tingle. It was quite strong in alcohol content, too - probably between beer and wine.
It was a big hit at parties.