Nest: The Learning Thermostat
It's practically guaranteed that at least one person in your household has the exact opposite thermostat preferences that you do. For those cases, there's the Nest ($249), a thermostat from a former designer for Apple. Sleek, well-designed, and easy to use, the Nest learns your behavior - recognizing that, for example, you wake up on Wednesday at 7, and on Saturdays you wake up at 9 (or 10...or 1). It can also email you reports about your energy usage, making your home smart and green.