A while ago we wrote about the Kill-A-Watt, a little device that allow you to to measure how much electricity whatever you plug in it uses. But since you can only test one appliance at a time, discovering the energy consumption of a whole house is not very practical. That's where this other gizmo comes in: The EUM-2000 is a whole house energy monitor. It can display the electricity used in KWh or in dollars (after you input your local rates). It costs US$200 and can be bought here.