May I recomend EverQuest?
One of the most addicitive games I think in history.
www.everquest.com
Its nuts and basically the game has saved me alot of money since I have no interest really in any other game since playing.
Mind you EQ is very difficult and a non-instant gratification game, it does however require alot of strategy and team work to get anything done with other players which is fun.
I've played 4 years almost 5 now.
Not to mention I have met many many adult webmasters while playing its odd but its true
(Not gonna mention who though since that would not be right).