This might be a hardware problem, might be a software problem. I've posted in Hardware to avoid the barrage of iTunes for Windows messages. Recently, I've had a lot of apps unexpectedly quit. It can happen when I'm launching a different app, or just for no apparent reason at all. Sometimes I won't even be touching the computer and it'll suddenly tell me that something has unexpectedly quit. Sometimes, it just drops out to a blue screen with no warning, then reloads Finder and all my startup items. Anything else I was running would disappear. And sometimes it'll drop me out to the login screen for no reason at all (I haven't seen it do this since removing my second user account - perhaps this problem and the one above are one and the same, and it's just automatically logging me back in since I'm the only user?) Now for the hardware side of things. I have an 800 MHz iBook (Nov 2002 version), which contains stock-standard hardware with the exception of a 640 meg memory upgrade I installed 6 months ago. I have noticed the hard drive getting quite hot recently, and the fan hasn't come on. And the weather's by no means cold here either, it wouldn't surprise me if my iBook's been subjected to 35-40º in the car when I'm driving back from classes in the afternoon. So has anyone experienced this sort of problem before, and any ideas?