Available while stocks last. I ordered mine online with other things to take the order over £35 for free p&p, also applied the "secret3" code for £3 off £30 spend (or secret4, secret5 for £4 / £5 off £40 / £50 spend, credit to andywedge for the codes).
Not sure if these are instock in many stores, but they seem to retail at £29.99, so about 66% off.
Not everyone can get the freebie energy monitors (unless on benefits *EDIT: or lucky customers of a generious Electricity supplier), so thought I'd share.
Also Maplin are selling a "efergy Infrared Standby Eliminator" (single plug, but you should be able to connect to mutli socket adapters) for £12.99.
Prolectrix Wireless Home Energy Monitor
* Monitor and calculate the cost of running your home or office appliances
* Instant and historical consumption data
* Memory feature stores data
* Day, week and monthly usage view
* Shows power usage in s, KWh and CO2
* Quick and easy installation with no expert knowledge required - simply attach the sensor and transmitter to your electricity meter
* Easy to use and portable display unit instantly tells you how much energy you are using
* Start saving money and the environment immediately
* High use warning alarm
* Fun and educational for the whole family
* Raises awareness as to the cost of electricity in real time
* Requires 4 x AAA batteries - not included (Order Code L42AL)
Smart meters, which measure your energy consumption, are a great way of keeping track of how much energy you''re using. When you can actually see how much carbon you''re wasting every time you switch on the TV or make a cup of coffee, it will make you think twice. The Home CO2 meter is a portable monitor you can take from room to room to see at a glance which appliances are using the most electricity. For every pound saved on an electricity bill, you''re also saving 6kg of carbon dioxide, which is what a coal-fired generating plant would emit while making this much power. The energy meter does not require you to carry out any electrical wiring. The clip fits on the external cable, which has a live supply running through. If you have any doubt about any connection or how to install it consult a qualified electrician. Both the transmitter and monitor are battery powered and require 2 x AAA batteries each, not included (order 1 of Order Code L42AL).
Also, if buying online don't forget the Quidco: 2.5% with voucher code or 6% no codes used.