I'm in the market for a Firewire hard drive, something between 250 GB and 500 GB capacity. I'd prefer a drive that can be powered by the Firewire port, requiring no other electrical power outlet or adapter. It seems that the available products are limited if you don't want the drive to be tied to the wall socket. Which drive should I buy? I almost bought a Lacie d2, but it seems to require an external power socket.