When I start to play, I just forget everything around me.
I started playing games when I was about 6 or so (Comm64), moved to PC when I was 9 with Sierra's KQ series, and when I was old enough that mommy wouldn't scold me for not being in bed, I just stopped going to bed (it always annoyed me, because what I would actually do was lie in bed, not sleeping, thinking about what I could be doing in the game).
Such an addict.
Now, I generally only play games when I have someone around to tell me to stop playing. But, when I do play, it will generally be with as little sleep possible. I generally try to beat most new games in less than 3 days.
Edit: Games like Morrowind and FF (and any MMORPG) are my enemy. I love them so much, though.
