Look up above this article. A little higher, above the screen. Chances are that if you're on a laptop or even one of many desktops made in the last five years you'll see a Webcam built in. And that Webcam might end up saving you--and the environment--a little bit of power.
British inventor and self-described "ecogeek" Peter Hopton and his company VeryPC have come up with a piece of software, called PecoBOO, that uses open-source face detection to detect when you're looking at you screen and, more importantly, when you're not.
When you look away for more than a few seconds, get up, or generally ignore your screen, it'll turn off. Then, when you face it again, it turns on. This reduces backlight power consumption and thus overall energy consumption of your device. That saves energy for your battery and your wallet.
The general idea isn't new; other devices have similar technology, like the iPhone. Its optic sensor disables the touch screen and backlight when you put the phone up to your ear. This is just a natural progression of the same idea, though the end effect is different.
I'll cop to being one of the people who disables the power-saving features of my laptop most of the time. Sometimes, as a writer, I have to sit and think for a few moments about how a paragraph should be put together. For some reason if my screen goes blank I find it very distracting, but if I had this built into my MacBook Pro, I wouldn't really have to worry about it.
Unfortunately, PecoBOO is currently available for Windows Vista and XP platforms only.
(Via New Scientist)