Last fight I got into was with Kevin Tealer. I was in 5th grade, he was in 6th. We weren't friends but he lived across the street from my best friend Scott Diamond, and about a half-block away from me. As I was walking home from Scott's house one day, for some reason Kevin decided to follow me and walk to and fro all around me, taunting me and calling me names. He was always an annoying asshole to me but he'd never gotten physical before, and I was ignoring him because I didn't really care what he had to say-- but then he got right in front of me and pushed me.
At that point my vision turned red, and I reached way back behind me and took probably 30 seconds to deliver the haymaker of a lifetime right across his jaw. I clearly remember having the time to look into his eyes, as he looked at my fist, and watched it all the way into his face. I didn't know much about fighting but my older brother had told me one thing-- aim behind where you want to hit and follow through. I cracked him so hard he literally flew backwards in almost cartoon like fashion. He didn't get up, and I was terrified and ran all the way home, shaking with fear and adrenaline.
I never told anyone about that day, but Kevin Tealer never again bothered me, for all the remaining years we both lived on that block.
And that was the end of my fighting career.
Unless you count the several times I got jumped by multiple kids in junior high because I was bused all the way across town for forced integration, and they didn't like any white boys on their turf and regularly beat up those of us who were smaller, simply because of the color of our skin.
But that's another story entirely.