Better than the Ebuyer post, if you want two drives and qualify for Free delivery via their partner forums.
Find in TODAY ONLY SUPER SAVERS:http://www.scan.co.uk/TodayOnly/Index.aspx
otherwise you pay full price
As hard drive capacities increase, the power required to run those drives increases as well. WD Caviar Green drives make it possible for energy-conscious customers to build systems with higher capacities and the right balance of system performance, ensured reliability, and energy conservation. - WD has reduced power consumption by up to 40 percent compared to standard desktop drives with the combination of WD's IntelliSeek, NoTouch, and IntelliPower technologies.