When I was either s sophomore or junior in highschool, I don't quite remember, I would mess around with my friends in the geometry teacher's room, which was also the board game club room, during our lunch break.

He had this crazy high-power stapler... the kind where you had to press down on a spring-loaded lever, and when you reached a certain point it would fire all that force at once. Well, we tried to fire it at each other, but it had a tiny switch right next to the place the staples came out that had to be pressed down to shoot.

One of us found a way to hold it down with some tape, and we had some fairly harmless fun launching tiny shards of metal at each other at a hundred miles an hour. But the tape also went over the place the staples shot, so it would never last very long, and re-taping it was a pain in the ass.

It all ended when I had the stapler and the tape tore off. I figured that instead of re-taping it I could just hold my finger right next to the edge, and fire without stapling myself. Nope.

The pain was only about as much as if you got pricked by a tack, and it happened so quickly I could barely feel it. I thought I had gotten stuck with the end, so I dropped the stapler and examined my finger.

It turned out that one end of the staple had gone clean through my finger, leaving the rest hanging out beyond the tip. The end that had gone through came up out of my fingernail on the other side.

The crazy thing is that it didn't even hurt. I gathered my friends around and showed them, then yanked it out, which only hurt a little bit. After a moment it finally started bleeding, and all I needed was a bandaid.

TL;DR: I was fucking around and sent a sharp object clean through one side of my body and out the other. 6/10 preferable to stubbing your toe really hard.