I had an uncle with the most usual nickname I've ever heard. "Appleknocker". he got it one day when the family was putting up hay, my uncle was sitting on the side of the empty wagon with his legs dangling over the side.
The brother driving the team of horses got too close to an apple tree and yelled for everyone to watch themselves.
My uncle didn't move and the tree hit his legs and nearly broke both of them, while knocking some apples off the tree. He always walked with a limp after knocking the apples off the tree.
My dad's nickname when he was a kid was Barney Google, because he had big eyes. It stuck with him all his life.