I'm thinking of using a 12" Powerbook as my main mac connected to a Flat Panel. It seems that most of the comments about heat are generated from the hard drive - is this right? If so would the following setup help? At my desk I run my mac on an external Firewire drive - backing up to my Mac HD regularly. Then intensive tasks are using the external firewire instead of the internal HD. Thus reducing heat within the Powerbook. When I need to go on the move ( i copy/backup my working files to the internal HD if necessary) I just unplug from my Flat Panel and firewire drive and I'm off. Work on the move is likely to be less intensive that the type of stuff I do at my desk. Any thoughts?