I am looking for a laptop charger that requires no power outlet but instead utilizes a usb port of another computer to charge my laptop. That is, I am seeking a usb-to-laptop port charger, NOT power outlet-to-laptop's usb charger. Is such a product even possible? I am guessing no since the usb port would not be able to supply enough electricity to power the laptop, even to maintain the battery (not charge it).