I got sucked into World of Warcraft a while back. I have spent way too many hours on that game, but it keeps me outta trouble I suppose. I must say though, I went through a rough mental addiction with that damn game. Feel free to laugh, but I am entirely serious. I was flunking classes solely because I cared about playing that game more than doing hw, studying, and sleeping. I lost a great job because I was sleeping a maximum of 3 hours a night. I started losing friends because it's all I would do on the weekends. Hell, I didn't even make an attempt to speak to a female on more than a friendly basis for months. I still play it for a few hours everyday, but I will always leave it for something more important now.
Anyhow, my MMO addiction is already spoken for lol.