High school, sixth form I think. Roughly seven years ago. My mates and I were goofing around with a half-size rugby ball, playing some kind of scrag. Anyway, my friend had the ball and was about eight feet in front of me. He kicked, but the ball didn't sail over my head like he planned - it went straight into my cods, and I could not stand up for several minutes.
It was a unique kind of pain.