Something you're just good at with minimal effort and/or you learned much more quickly than average.
For me, it's paper snowflakes. My brain just seems to effortlessly figure out what cuts to make to the paper wedge to make it turn out exactly how I want it. Largely useless, but good fun and was a much-needed ego boost when I was a kid :]
I'm polarizing, both in a good and a bad way, and I always have been.
No matter where I've been or what I've been doing, people tend to remember me. I've ran into teachers decades after I was in their classrooms and they instantly called me by name and remembered something I said or did in class. Same thing with old jobs. When I started teaching, some of the office staff instantly said "welcome back!"
Even casual acquaintances seem to pick me out quickly. Last week a random person I admittedly didn't remember myself said "I remember you at Borders" (back when that bookstore chain existed) and remembered an argument I made and how heated it got about what was (at the time) my controversial opinion that refinancing mortgages was a very bad idea and the fact they were so aggressively pushed on TV was a sign that the entire thing was going to go tits-up. That person remembered my opinion because they were mad at me for saying they were making a mistake... and they wound up being between one house they couldn't sell when the recession started and another house they could no longer afford to pay for that they were trying to move in to.
I didn't hold that over their head; actually I was glad they crawled out of that mess and were doing better. It's harder to be mad at people in person.