My little Mac Book does a pretty good job of running my "at home" applications and doing so without getting too hot and noisy. However, every now and again it ends up sounding like a Spitfire about to take off. What I’ve noticed that is that in the majority of these cases there is nothing running that should be stressing the system out, however, the one common item is that OSX is waiting for me to acknowledge a dialog, e.g. there is a update for xyz do you want to download it? Simply dismissing the dialog turns the Merlin engine off and taxes back to the hanger. So is there some bug on OSX that gets the UI into some kind of tight loop waiting for a response? If so this could be pretty serious for any sort of server application that could be starved of the processor, or at least sucking power.