I've only met one, TigerFan (Lisa). She had an extra PS for Cinderella's Royal Table that she gave to me. Since she, Lynn and Emily were going to be there at the same time, I was on the lookout for a green ribbon. I never saw a ribbon, but as luck would have it, she ended up asking me to take a pic of them. After talking for a minute, I figured out who they were. It was great to meet them!
I also briefly met a guy at Epcot who posts exclusively on the pin trading boards. I don't remember his name, but he saw my greeen ribbon and asked if I were a DISer. He had HUNDREDS of pins on a vest he was wearing.