I'm currently addicted to Assassin's Creed ... >.> I've wasted so many potentially productive hours on that game!

I also enjoy PC-gaming a lot, especially the civilisation building games like Age of Empires, Rome Total War, the Civilisation series!

I used to play WoW and I went through a long phase of playing Evony, but I weaned myself off them out of necessity last October. Any game that you can't pause has the potential to become overly addictive (even more so than something like AC) and since I have a slightly compulsive/competitive personality anyway - best avoided!