If the government is serious about reducing energy usage in the home, then they should provide one of these monitors for every house.
The only drawback is that you become a little obsessed with how much energy your appliances are sucking out of your bank account, and you are continually going around the house turning things off. You know straight away if the kids have left the lights on in their bedroom, and how much it costs to have a shower.
It's so easy to install - just fit the sensor clip around one of the cables going into your consumer unit, turn on the sender box and the remote monitor, and you're ready to find out how expensive your tumble drier and washing machine are, and more importantly for me start turning lights off (halogens are costing me a fortune in electricity).
I just wanted to know how many kilowatts we're using in real time and how many units of electricity (kilowatts/hour) it's costing us, which this unit does fantastically. You soon find out what appliances are costing you the most money.
Buy one, become obsessed and save some money.