We've installed many "smart" lighting control systems.  They involve replacing the switches with either hard wired or radio frequency controlled light switches.   Great system, with energy savings, convenience, eliminating multiple switches with one clean looking programmable switch with "scenes".    This costs about $40k to $60k all in for a large home. Here is Phillips Hue, where the wireless lighting control is actually in the BULB.   Of course this means you have to have your smartphone with you to control the lights.   Interesting.