"Just in case your mates are skeptical, you should actually buy an Efergy Elite. It is an energy use monitor that will record every watt you use. This way, when you mates ask you to prove your point, you just show them the numbers and "Bang!" you've started a revolution. You see, most people tend to ignore what they do not see. With an Efergy Elite you will see the results. This way you, your family and your mates will be able to track the results and feel more involved. They will go out and buy their own and you can have a contest. You'll have intelligence in the war on global warming."
More at Alternative Energy Centre.