Its not my most painful experience but it one of my buddies.
Imagine you have a smart ass idea to fire a bottle rocket up between your legs and into the air. Imagine the Person firing the bottle rocket is stupid and lit it at the wing angle. Now Imagine said bottle rocket taking a sharp turn, shooting through the crotch of your pants, and then exploding. Yeah. Imagine how hard I was laughing when I was the one who lit the bottle rocket.