At $50 a switch, WeMo (Belkin) makes an outlet switch (plugin) that can be controlled via WiFi. And now they have a lightswitch that does the same thing. This is the better way towards home automation than the other existing methods (X10, etc) which either don’t work well, or tie you to a given company and cost a fortune. Of course at $50 a whack these are not cheap. But at least its using more common tech.
http://the-gadgeteer.com/2013/10/07/now-you-can-control-your-light-switches-with-wemo-controllers/