Around 11 years old or so. I wanted to make one of those soccer balls with a rubber band.

But I had no rubber band. Or a way to properly fixate anything to a ball.

So I took some nylon string for kites, tied it around a 2cm nail and stuck the nail into the valve of a soccer ball.

Tied the end of the string to myself, kicked the ball, the string made “twang”, and the ball rolled off.

I was annoyed that it didn’t work. So I followed the string from the end that was tied to myself… and found out the nail was stuck a cm or so into my upper arm.

Pulled it out and it didn’t really bleed much or anything. Never told my parents about this.

I was very stupid and very lucky that day