I don't have any really crazy MMO stories, I've never been too far into them, but there is one recent experience that I'll never forget.
I had only started playing Archeage for a while when I decided I'd join up with a clan and start really getting into it all. I found one group that seemed fun, made an application on their site and just waited to see what I'd get back. A couple hours after that I was exploring along the edges of the map, to see if I find any interesting stuff, or illegal farms with anything worth stealing. Lo and behold I found a massive tree farm just sitting there with a couple of minutes left before it was ready to harvest, so I decided to just wait it out and take it all for myself. Once it was ready I was about to get to work on it when suddenly I see a good 10 people rushing up my way and crowding up on me. They started talking to me and asking what I was doing there and I tried to play it off when I went a realized they were the same group I had applied to earlier. Decided to try and use that to get away with it and they laughed it all off.
Ended up joining with them and becoming somewhat of a specialist, finding how far you could push map boundaries and where best to hide clandestine crops and not get found. Fun times, though the game ended up being a flop for most of us with the way game progressed.