This is the cheapest one i have found on this.
£112.49 with RELAUNCH091214 code
2TB - good machine
Hitachi SimpleDrive Simply better external storage and backup. Plug n play, Turbo-powered USB 2.0 (for Windows); keeps your data moving up to 25% faster.
Simple plug 'n' play add-on storage
Sits flat or stands upright with included cradle
Built-in cooling vents for quiet, reliable performance
Automatically powers on or off with your computer
No engineering brilliance required. Just plug it in and youre ready to store your capacity-hungry files. Affordable and reliable