The WD My Passport Edge is a nice external hard disk with decent performance. It's compact and light, and comes with lots of useful software. It's a good option for an average price of £72, even if we would have liked to see better performance.
Slow computer got you down? Maybe a hardware upgrade should be in your cards, if so this guide to the Fundamentals of Upgrading a PC is an invaluable read. PCSTATS Tips