A couple of years ago, Seth Frader-Thompson was driving a Prius. Priuses have little screens on the dashboard that tell you what gas mileage you're getting, in real time, as you drive. It crossed Frader-Thompson's mind that houses should have something similar. So he built the EnergyHub Dashboard, a little device, with a screen, that can talk wirelessly to your furnace and your various appliances and let you know exactly how much electricity (or gas) each one is using and how much it's costing you. It can also turn appliances on and off and raise or lower the temperature in your house so you can rein in the real power hogs. EnergyHub is currently partnering with utilities for trials and will be available direct to consumers in early 2010.
The 50 Best Inventions of 2009
From a rocket of the future to a $10 million lightbulb, here are TIME's picks for the best new gadgets and breakthrough ideas of the year