Well, here are three outlets for $22.
http://www.amazon.com/Etekcity%C2%AE-Wireless-Controlled-Ele...
And here is a project for them:
http://www.instructables.com/id/Raspberry-Pi-GPIO-home-autom...
X10 powered sockets are $20, and do exactly what you described, yet don't have wide adoption at all.
Re:Arduino Yún – combining Arduino with Linux
by wiredfool on Tuesday May 21, 2013 @04:59PM
(#5746788)
They've been around forever, and I dismissed them back in the internet dark ages because they only had crappy windows software and their obnoxious intrusive ads seemed to be all about "security" cameras pointing at scantily clad women.
/me realizes that I've just dated myself here.
Lets think of one device, a relay (or solidstate relay) that controls an outlet.
You need:
A radio, or a powerline networking unit ($10). Some sort of processor ($45 for a Pi w/ps and sd card). Some low level logic to connect to the relay ($.25), the relay ($2), and the power socket ($2).
If you want to control two outlets at one place, you're only duplicating from the low level stuff to the power socket. That's another $5.
If you want to do this at a location that's more than a usb cable away from site #1, you're in for another $50.
The holy grail here is a wifi enabled power socket. All it needs is a small api: status and on/off. Bonus points if there's a current sensor. This could be done with the processor from Bunny's $12 phone and the power relay bits.
But, it's got to be priced in the $10/socket range.