FireWire 400 socket into a USB port, but for all intents and purposes here, it does as much. You see, Scosche's Passport was designed to channel the energy from older FireWire-based iPod charging gear into the USB prongs that the newer iPhone / iPods only accept. Macworld was able to get ahold of one for review, and in testing, it found that everything worked well when toying with new iPods, and while it was designed specifically for in-car applications, critics found that it even worked (albeit inelegantly) with dock-cradle accessories. Was it worth $30? Absolutely, so long as you'd rather burn $30 than replace that mess of wires you've got behind the dashboard (and you would).