A couple of months ago I ran a Roll20 EoFF D&D game. There was a ghost who was crying over an empty crib about a missing baby. Anyway, they had the great idea of putting the tiny Gnome Wizard (Shauna) in the crib to pretend she is the baby.
And then, for reasons best known only to herself, the Dwarf Barbarian (Jinx) decided she wanted to slap the baby to see what the ghost would do. So I made her roll for it. And she got a crit.
It was the best/worst thing I have ever seen in a D&D game.