It's especially bad since I'm in my hometown. He said his first name, but I knew so many people with that name, most of which I haven't seen in over a decade. And for some straaange reason, a lot of people don't look the same when they're 18 as when they're in their mid thirties!
Mystery solved! One of my high school bullies who has obviously done some growing up because he actually came back up and apologized. Which was super nice.