P3 International P4400 Kill A Watt Electricity Usage Monitor

This product was very helpful, on the first day, I went through the whole house including the garage and checked every outlet. in some cases I needed an extension cord to be able to use the tester over a period of time. You can set it up to calculate how much energy is used over a period of time like an hour or several hours. I noticed that by turning off the directTV box with DVR that we could save over 100 watts per hour. We used to leave it on all the time but not any more. Also an ordinary DVD player used over 100 watts per hour in standby mode, it looked like it was off but still used energy. we used a power strip and turned the switch off. I was surprised that a window air conditioner used almost the same amount of energy between low medium and high. Some computer related stuff like monitor, printer, cable modem, etc used energy all through the night even when we weren't doing anything. there is a power strip device that senses how much energy is being used during normal operation and when you turn it off, it will power down the other outlets. I will be buying that next.

does what it made to do but could be smaller/more user friendly, It meets my intended purposes and I would buy one again

works well, as advertised. Very easy to use.
My gripe is that it cannot handle larger loads >15 amps or 220 volts.
Would be nice if it was 110/220 compatible.

Works marvelously. It's reassuring to know that my iMac with an extra display and various gadgets only draw 125 watts. The digital display reads power with enough sensitivity even a small accessory's power draw shows up. And if you want to know how much your cell phone charger draws, it reads even very low power draws.

--Mike Perry, Untangling Tolkien: A Chronology and Commentary for The Lord of the Rings

I have nothing to add to the reviews that are already here but I do wish to pile on with a 5-star rating of my own. This is hands down the most-borrowed thing that I own. When I tell people how it more than paid for itself the very first time I used it (found a unused device in my house drawing a constant 40 watts- unplugged it and saved at least $25/year), they are intrigued. When I tell people how I used it to size things to plug into my generator during the massive power outage of hurricane Ike, they nod their heads in understanding.

A great product: if I were president one of these would be mandatory with every electrical hookup in America :)