PS: If no PDA/cable will do this 'out of the box'... do you see any reason a 'Y' cable (serial AND USB connections) can't plug the serial connection to the PDA -AND- the USB connection to a (live) USB/cigarette lighter adaptor AT THE SAME TIME???
PSS: The goal is to hardwire PDA to my car's diagnostic port. All automotive diagnostic (at least OBD-II diagnostics, for those in the know) PDA connection systems MUST use a serial connection between the car's diagnostic port and PDA to work. None can provide power via this serial connection... since the goal is to hardwire the PDA, I need to provide power/recharge via the car's electrical system and at the same time have the serial cable connected to the PDA.