At work, we ordered several pizzas. H (brilliant young engineer) shared a pizza with me, and we decided to store the leftovers in the work fridge.
H: [coming back from the fridge] "The large pizza box doesn't fit. I need to transfer it to the smaller box.". [opens small pizza box, discovers there is still pizza in it] "I need to swap these."
D (intern): [getting up with his own empty pizza box in hand]: "You're going to need a temp box. Unless you can XOR pizza."
Later the interns sent me a reddit thread about top revenge stories, and I spent one hour reading it, riveted.