I've done alot of the benign ones. Kicked a ball and hit myself with it, check, stood on a ball trying to do fancy tricks and faceplant, check, tried to be fancy and jump right back up and hit my head on a table, check.
I've done some stupider stuff, like getting rolled up into a ton of blankets and pushed down the stairs and unavoidabley hit my head on a barstool. Those were actually fun times, who would mess around on skateboards you break ankles and shit. Oh and I've ridden a kids tricycle down a set of stairs and hit my sister when I fell off to the side. Are all kids this terrible? oh noes.