I'd say a pizzabox would definitely be the smallest desktop form factor (excluding the monitor), but if you want a built-in monitor for convenience then you should take a compact Mac (128k, 512k, Plus, SE, etc.). Color Classics are larger than the other compacts but your requirement for colour output makes them the only compact that you could take. Personally I would take a slightly larger Mac in order to get a better monitor than to take a Powerbook and have to make do with the small screen size and narrow viewing angle, but the choice is yours.