I recognize people from the German subforum from time to time
Oh, and on the EN forum there was a player once who kept on lying about the state of my server so because he annoyed me so much, I remembered his name involuntarily. Then, of course, in my next Coil farm party, I met him there xD
Didn't say anything though, but I might have left that party faster than normal.

Personally, I got tells in the past from people who wanted to tell me how much they agree with something I said on the forums (but appearently without making their opinion public themselves by just replying to the thread..xD).
But it's not like I ran into them on the streets, they just looked my name up in player search.

Hm..the funniest encounter was when I was bitching about a Void Arc run in the duty finder complaint thread, but was super happy with the healer who joined after we got rid of our horrible one (or something like that, I don't remember it that well xD).
Especially how he gave me (ninja) AAAALL the good cards
...turns out he remembered me from the forum and was happy to see me while I didn't recognize him at all xD Of course, in the complaint thread, he answered next and told me "yeah, I was that healer"...kinda awkward :x