While D&D-like RPGs are of my favorite topics the one that tops that is talking about myself (and my wife) so I'm going to share with you all here.
I met my wife through an online dating site. We hit it off amazingly well, funny part is we were missing each other by one connection for years.
Two of my LARPing buddies when I was big into that stuff were co-workers and work chums with my future wife.
Years back one of my buddies and she were still in college and my friend was dragged to a friend of a friends house to meet her during a break in college, that friend of a friend was my future wife; they missed each other due to some travel problem but my friend still ended up visiting my future wife's home and meeting her mother.
My wife is and was a horrible nerd (she used to be an admin of a Dune mush) she was into onlien free-form roleplaying. One of my oldest friends was also into free-form roleplayign online. I just recently discovered my wife and friend knew each other by AOL login names and free-form gaming years before we met.
We missed each other at parties either one of us showing up late and the other leaving early. I think my wife and her first husband were both in a game shop once talking with the owner who I knew when I was thee chatting with one of the other employees while shopping. We both shopped the same game and comic shops but never bumped into or noticed each other (beyond that nagging recollection i just mentioned).
I'd almost think there was some sort of conspiracy or even fate at work but I suppose in a world with over six billion people it's still possible for it to be a small world.