Want to control your room lighting using your computer? Then buy some triacs and opto couplers, build this gadget and plug it into your PC parallel port and voila!
http://www.raphnet.net/electronique/triac_lights/triac_lights_en.php
Information about digital communications including, computer, Internet, telephone and television networking over common household power lines.
http://www.powerlinecommunications.net
Design and installation of home network systems for lighting, audio, video, home theater, telephone and security.
http://www.ehchomes.com
http://www.qsl.net/vu2upx/Projects/home_security.htm
Gadget lover's page, featuring a program (heyu) to operate the X10 CM11a interface from a Linux system.
http://heyu.tanj.com/heyu/index.html
The security system application and program offers a simple demonstration of the BASIC Serial Interface. By adding only a few door and window switches, a transistor, a siren, (see schematic) and a few lines of BASIC program (see program listing) the interface can become a multi-function security system.
http://www.jbgizmo.com/page3.html
A very nice home automation project. Control every device using a personal Computer
http://www.aaroncake.net/circuits/crombuld.htm