Ah, the memories. Almost anyone who has worked with machinery and such other stuff with bolts and blades and fire has a slew of tales to tell. I hit my elbow, actually the back of my arm just above where the elbow flexes, on the pointy end of a 5/8 drive bolt one time; made me lose my breakfast. Got whacked on the elbow by a fan blade running at about 1200RPM - said "owitch" and a few other things nice; when I got my vision back, there were a couple of ladies standing in the station drive with their mouths hanging open, and looking like they wanted to flee. Just recently, I split my left pointer finger thru the nail clear up to the first knuckle by getting it in the way of a drill bit as it grabbed and popped trough a sheet metal piece; it doesn't look like it will ever get "normal" again. As with many other pursuits, there are only those who have, and those who will.