What is X10?
X10 is a communications language that allows compatible products to talk to each other via the existing 110V electrical wiring in the home saving both time and money. The technology is widely used and accepted. X10 devices are typically inexpensive. PC to X10 serial converters are normally less then $50. Once your computer can talk through X10 any other X10 device plugged into the house can be controlled. Examples are Lights, security systems, sprinklers and air conditioning

What is a smart home?
For some, it could be as simple as automatic timed control of a few lights and appliances. For others, intelligent security features may be the most important. Whole house audio/video is another feature that can make your house smarter.

Why would I want this?
A smarter house saves energy and helps the environment through intelligent control of lighting, heating and cooling. A smarter house can protect your family and possessions from crime through sophisticated security and surveillance systems. Home Theater systems allow you to enjoy music and video from anywhere in your house. The elderly and disabled can have full control of the home from their fingertips.

ESXManager is simply a software interface for X10. Once you have purchased the Serial to X10 module you can purchase any X10 device.

For more X10 product check out these links
http://www.smarthome.com/
http://www.x10-store.com/
http://www.x10ideas.com/
http://www.letsautomate.com/