That Tekkeon seems like a god idea. However with an iPhone & a car charger adapter for it I can use my PT while driving with it. It would be pretty nice to have though expensive. I'd go for it if I knew whether or not it would charge my MacBook too- I can't seem to figure that out from my minimal research on it. Do most of Tekkeon's power packs give you the ability to adjust the voltage output or just the more expensive ones?