With everyone trying to save a buck or two, this simple inexpensive device can save you more than it's cost by telling what all that electronic and electric stuff in your house and shop is costing you. Did you know that even leaving a simple cell phone wall charger plugged in (without the phone) draws electricity?
I have several electric heaters for on the spot instant and location warming (the wife gets cold easy), so I plugged them all into the Kill-A-Watt and was surprised to see the differences in energy draw between the various designs (oil, radiant, quartz, etc.) How much juice does that air compressor draw every time you run it? (Haven't tested mine, yet, but will.)
URL for the company info page: http://www.p3international.com/products ... 00-CE.html
The best price I've found for them is here: http://www.newegg.com/Product/Product.a ... ill-a-watt
It's not an everyday tool, but definitely something to keep in the house or shop to help keep a check on your electric bills.