EcoDog's FIDO home energy monitoring system monitors individual circuits in your home at your electric panel and uses power line communication to get the data back to your computer.  Unlike other monitoring systems that send data over the internet, this data is is sent to a software program that resides on your Intel-compatible PC running Windows (not too easy if you have a Mac).  This means there is no monthly fee for software hosting, but also means it may be difficult to access your home's energy data from a mobile app or another computer.