Personally I think about staying logged but since I have a slightly older mobile video card, my room will be forever noisy and uncomfortably hot with no AC on. But that's not the main reason. My main reason is that there really is no reason to just randomly go AFK for No Reason, so I log out and hopefully a poor soul can get a few hours of game time in while I come back and whine at myself for being a goody goody and logging out. But you know what? I see it as letting someone else get a chance to play while reminding me that well it's a game and there are other things I can do.