Flock Step lockstep
When you're taking a piss in a bathroom stall but the door's lock is broken, so you stand on one leg to pee while the other is holding the stall door back. Named after the Rhythm Heaven Fever game Flock Step.
"The urinals were all being used, so I had to use the broken stall. I ended up doing the Flock Step lockstep, and I practically pissed all over the room."