According to Nest, the thermostat takes about a week to start picking up on your routine, at which point it adjusts the temperature accordingly. It knows, for instance, that the whole family's out of the house by 9am, and that people start trickling back in around four in the afternoon. That's all thanks to a collection of six sensors, which keep tabs on metrics like temperature, ambient light, humidity and motion -- whether it's fingers about to touch the display or people passing in and out of the room.Uses wifi, works with your pc or iphone/pad, priced around $250, very slick!
Update:
It is COOL (I got one!)
Unfortunately, it's so cool that Honeywell wants to sue it out of existence.