[ktsmith]

I'd take that a step further and put a sensor on every outlet so it would be like a built in kill a watt that you could look at from a household level, circuit level, and then socket level. You could monitor and alert on things that are suddenly using more or less power and also determine where you are losing the most energy to unused or seldom used devices that are always on.

[ChuckMcM]

This is something I've looked at. When outlets with built in USB charging ports came out I thought, "Gee it would be much nicer if they used some form of powerline networking to tell the house server how much power they are supplying."