I've seen some incredible matchmaking in the Call of Duty games, where when the final score comes up it's a difference of literally 1 point and everyone in the lobby is just in awe until someone says "...wow, that was a really good game." And everyone agrees "yeah, that was a really good game."

I joined the middle of a Counter-Strike: GO round and was the last one remaining and dudes were like "WOAH LOOK AT THIS GUY WITH THE C&C95 AVATAR!!!" And once I got a couple kills (didn't win the round) and they saw my old-school CS tactics I could hear them saying "yo, i actually really like this guy!!!"

Similar to Pete, I actually had someone invade my Demon's Souls game and I was on the Chinese/East Asian servers. I was completely freaking out and tried throwing a cheap shot at him and running like hell, but he just kept waiving and ended up helping me out, which was good because I was a little underleveled for the area I was in...

My only interaction with the incredibly strange world of MMO Love was in EverQuest, I was in a Dark Elf guild and one of the girl members who was out in our group started telling me I was cute...

A little while ago a max level dude was giving out free bags and balloons in our WoW server, that was pretty nice. Actually, almost everyone I've met Dungeoneering in WoW has been very, very cool, and I've gotten into some pretty chill lobbies in Diablo III as well. I guess I'm just lucky when it comes to Blizzard games.