I'm sure my family could make use of something like this. Oh sure, we try to be pretty careful about turning off lights, but every so often we leave a light burning for days in the basement. And of course, there's always a handful of appliances -- a stereo, a modem -- that suck a bit of power whenever they're plugged in, even when they're off. (For most models, for example, the clock on the microwave uses more power than the oven itself.) But plugging and unplugging all these appliances from the wall is a royal pain, especially since we have kid-safe protectors on all of the outlets. A universal power-off switch might save us five bucks or so a month on our power bills.

Unfortunately, retrofitting my entire house to take advantage of this sort of switch would probably cost more than the energy I'd save. But at a minimum, the idea of a whole-house off-switch is a good reminder that there's plenty of waste left in the energy system -- meaning that, in theory at least, we hyperconsumptive Americans could cut way back on our power consumption without affecting our lifestyles one whit.