A number of companies have worked on this problem. Intel famously sunk quite a bit into it, and failed. A few products with limited goals, like TheEnergyDetective.com exist. Some startups have come, run out of money before they got very far, and have gone. Others are still working on it.
These efforts have mostly been driven by observations in the 1980s that you can easily see the pattern of many appliances switching on and off, just by looking at a plot of a home's total power consumption against time. Automating this, and making it accurate is still a work in progress, and I think it will get harder. As others have commented, the increasing use of PFC and continuously variable drive motors, is making the power profile of appliances more bland, rather than more characterful. If you can identify anything, it might be more likely that you can say "A device with a model xxxxx PFC controller just turned on", rather than be able to say "An xxxxx just turned on". Being able to reliably identify a few high consumption appliances, like heaters and air cons, seems much more likely than being able to break down everything in the house.
If you look at the web site they talk about going from a poor power measurement unit, to a good power measurement unit, to a unit which can break down the power spectrum. This doesn't sound a lot like people working at the advanced end of the power metering business.