Well I mean, I'm a lawyer and I'd argue that I'm one of the, I dunno, maybe 500 best people at copyright law in particular in the USA. It's my career, my particular specialty, I've done some cutting edge stuff on it, and I've sunk well over the 10,000 hour number into it, I feel like I'm pretty good there. I dunno if my career really counts though.
Outside of that, I'm a pretty good French Horn player. Good enough that if I practiced really hard I could probably join a professional symphony, though I've never had the drive for something like that. But I'm good enough to pick up and casually sight read most French Horn music with minimal errors. I'm also consistently in the top 1% of all Hearthstone players worldwide (a videogame made by Blizzard Entertainment), so I think that's pretty solid.