Seagate FA Go Portable 500GB USB 2.0 Hard Drive on sale at Play website.
Available in Silver/Red/Blue colours.
By far the cheapest available price for this model.
This was posted for £49.99 about a month ago and is now on sale for £44.99. So hurry up as the stock might run out soon.
PS: This item comes without the docking. Just the hard drive.