Everyone wants to cut their electrical bill but it's often difficult to tell which devices are using the most power. According to the Electric Power Research Institute, the typical American home has 27 devices that are always on. But fret not, homeowners. According to this piece in The New York Times, new technology is coming down the pipe to monitor how much energy each appliance uses, including your HVAC system. The cost of these systems used to be prohibitive, close to $30,000 for some, but now technology is coming in the $495 to $695 range. Some analysts are expecting a boom in this technology known as "smart metering" and predict the market will spread to 52 million households nationwide by 2013.