Can the A500 charge through the mini-usb port? Or is there/will there be a mobile charger for the dock port? I think this is a real over sight that would make me a bit nervous taking the A500 on any long trips. Other than a car charger I also have an external battery that accepts a usb cable to charge my iOS devices. This could also charge the A500 if there was a USB to dock port cable. If anyone know of where to buy such a thing or whether it's planned for the future, I'd appreciate and info. Thanks!