The Energy Owl is a home energy monitor that attaches to the meter outside your home and displays data through a PC interface. 

From the How It Works section:

"The Energy Owl E.M.S. simply "watches" your electrical meter using an optical sensor. The scanner sends the data to the desktop hardware which then either transmits the data to your PC or stores it for later retrieval. When the Energy Owl software is open, you get real-time data, updating itself once a minute. In the event that your Pc is off, the hardware will store the usage data for up to 10 days. Whenever you open the software, the data will automatically be downloaded from the hardware and be permanately stored in the Energy Owl Database!