I don't, sorry.
I've seen it ruin too many relationships and lives so far with my friends and acquaintances.
While I know that not everyone is a candidate for addiction to a video game, it's still possible to get caught up in something you enjoy.
For that reason, and the fact that I normally hate cooperating with other players (I play MapleStory, but I solo. Go figure..), I can't normally play MMORPGs.