Yes there is 1pin on the Firewire 400 port that provides power to Fire wire 400 devices 6 pin to 6 pin (FW 400), and 9 pin to 9 Pin (FW 800). The other pin is a ground. However the mini firewire 400 cables (6 pin to 4 pin) just provide data and nothing more. That's why most devices like iPods and some USB external drives etc come with USB cables to use the power from the USB bus on your machine.