I too would be interested to know this. Also, as I understand it some of the newer N series phones (I have been told definitely the N85 and N86 but not sure which others) can be charged from a USB port on a computer but only if the battery is not completely dead when beginning charging. Apparently if there is no power at all you can only get the unit to switch on by plugging it into a mains socket. Has anyone experienced if this id the case with the N900?