Freecom Classic 500GB External Hard Drive - £63.44 delivered @ ebuyer !!
FREE supersaver delivery. Cheapest price I've come across for 500GB external HDD.
Description : No need to open your computer; just plug the Hard Drive into the USB (2.0 or 1.1) port of your PC or MAC and you instantly have a substantial increase in storage space. The Freecom Hard Drive is pre-formatted so you're ready to use your drive seconds after connecting it to your computer.