The "Meat Grinder"
Oh, the memories!
When I was about 10 years old my family was visiting some friends who had one of those old sit-down stone grinding wheel similar to this pic out in their workshop...
I was seeing how fast I could get it to spin when my mom called to me from the house. I turned to see what she wanted and when I did my left hand got bit by the wheel halfway from the base of my thumb to my wrist. It just ground a groove about an inch long that started bleeding all over the place. I ran into the house and my mom grabbed a bottle of alcohol and poured it over the open wound to clean it out.
I remember wishing someone would just cut off my hand since I didn't think it could have hurt any worse than that.
Never did go to the doctor. Just held it closed with adhesive tape until it healed. Luckily no structural damage was done.
Still got a nice little scar on my left hand.