I spent a while trying to find a good external HDD and this was the best I could find:
Western Digital My Book Studio Edition 1TB Firewire 400: Amazon.co.uk: Electronics & Photo
I was thinking of a Time Capsule also but I found them a little too expensive for what they were and the wireless feature I wouldn't use anyway so it seemed like a waste
The WD is 1TB, has Firewire 400, 800 and USB 2 connections with cables included
Another feature that I found attractive was that it turns itself off when not in use
Hope this helps