My Balls have never struck at me. However, my wife's African Grey barely tolerates my existing and likes to take stabs at me when he can. Gave me a really bad bruise once.

The worst I ever had from from my deceased Iguana. He was around 5ft at the time (got to 6ft before he died). I still have the scar on my middle finger. It was accidental too. I was putting a food dish in his cage and I guess he was just really hungry and ran straight the dish and bit the dish and my finger at the same time. He immediately let go and went after the food.