Which GM's have you met in person?
I played GM Jan Gustaffson when I gave a simul against 20 GM in Germany. I played 20 GMs (Najditsch, Rapport, Lagrave etc etc.). He was the only GM who won his game against me...
I'm kidding it was Gustaffson who gave the simul. He crushed me...

I met and played against Daniel King many years ago, he was the British GM at the time and a really nice guy too

I'm going to stretch the topic a little because my parents were friends with a British IM (not GM but he did beat Botvinnik and had been British Champion) in his 60s in our village who it turns out was once a codebreaker in WW2 (google Bletchley Park and GCHQ). He never mentioned it and they only found that out when they read his obituary. Apparently he was never allowed to play in tournaments in Eastern Europe in case the KGB got him. Dad always said never judge a book by its cover because of this.
Which has nothing to do with this discussion ... sorry!

I met Wesley So under very unusual circumstances. I used to be a freelance musician, and I was playing at a church service one Sunday morning. As I looked through the congregation I saw Wesley's face and recognized him immediately. Walked up to him after the service and chatted with him and his parents for a while. If I remember correctly it was like a week before Tata Steel like 2 or 3 years ago. He's an extremely kind and humble person, I was so glad I got to meet him.

I met Wesley So under very unusual circumstances. I used to be a freelance musician, and I was playing at a church service one Sunday morning. As I looked through the congregation I saw Wesley's face and recognized him immediately. Walked up to him after the service and chatted with him and his parents for a while. If I remember correctly it was like a week before Tata Steel like 2 or 3 years ago. He's an extremely kind and humble person, I was so glad I got to meet him.
Nice.

Also had the misfortune of meeting Finegold, around '86 or so.
But that was long before he was a GM. Or even an FM.

Got my picture taken with Yasser Seirwan at the US championships, last spring.
Awesome. Yasser is one of my favorite GM's.
Finegold, Erenburg, Oratovsky, Bryan Smith. A bunch of others like Kaufman, Ringoir, Kraai, and Paragua often play in the open tournaments around here but I've never had conversations with them.