PC World have a "Maxtor" external USB HDD for £79.99. I bought one, it actually has a Seagate (320gb) 3.5" IDE drive in it

Been fine tho - I ripped the drive out and stuck it in my PC but put an 80gb drive back in the enclosure, and it's been fine, as quick as fook to copy to aswell when using USB2 (under 50secs for a 700mb video file - 1.5gb in under 3mins)