I keep my MBP closed all the time, in it's case. (I use it as a desktop). Sometimes, after running for a long time, it will shut off. I mean instant off, like*snap* off (without a noise). Could this be because I use it with my 24'', maybe some monitor out issues? Do you think it's overheating (it gets ***** hot!)? Has anyone else seen this, maybe with a powerbook?