early days of aviation
Back when flying was new, guys would dress up like pilots, pull down their pants, grab a fake propeller, and bounce like a crazy man, making their soft wieners spin like a propeller. Girls could do it with their squishy boobs.
My grandfather did it at a family dinner and got called a 'flying donut.'
My sister did it at a concert and got booed by the crowd.
My friend did it in the park and got a free ice cream.