Wattson price plummets below £100

Since it launched last year, the Wattson 01 energy monitor has fast become the iPod of the green gadget world, inspiring technolust and cutting bills. Today, it's taken an iPod Shuffle-like step to affordability, dropping its price from £150 to £99.95.

It's still twice the price of this one, but you get what you pay for. While its rivals -- OWL, Efergy and Eco-Eye --- are all comparatively butt ugly, this is a beautiful bit of kit.