Usually these are sold for around $25-30 and many of us have at least one, monitoring some 110V charger or other appliance. These have a nice digital readout, and are quite useful in telling how many Watt hours you have used. Seldom are they this cheap, and with free shipping, it is a good deal. I have no commercial interest in Kill A Watt or in Tech Bargains (the advertiser) or NewEgg (the seller), but here is the ad notice:
http://www.techbargains.com/news_displayItem.cfm/286641
