Kill-O-Watts are these handy little machines that you can plug appliances in to and get a reading of how much energy they actually use.
The Canton Public Library (Michigan) checks them out to library patrons for one week at a time. They are a hugely popular item at the library. Read more about the Kill-O-Watt project at CPL here:
http://www.cantonpl.org/blog/green/environment/kill-watt-energy-meters-available-check-out-cpl
