That's all well and good, but for some people its intimidating and requires too many pieces of equipment. I've talked to many people who just give up at this point.Many of people would like to have a light (or a fan, or a radio, or other appliance) turn on when they enter a room, but they don't know how to easily make it happen. If you look online, or in a book about home automation (such as Smart Home Hacks) you'll probably be steered towards an X10-based solution.
That's all well and good, but for some people its intimidating and requires too many pieces of equipment. I've talked to many people who just give up at this point.
Luckily, there's a simple solution to a simple problem. If all you want to do is turn something on when a room is occupied, use the SensorPlug Motion Detecting Outlet.
You simply plug the appliance (500W max) into the SensorPlug, plug it into a wall outlet that's positioned where it will "see" activity in the room, and then turn on the appliance. If you want to get fancy, you can set it so that the outlet is activated only when its dark, and set how quickly the outlet is turned off when the room is empty. Simple and smart.