Hello everybody.
I have seen that you are looking for a solution to control your lights through ZigBee and Arduino. I can tell you that I developed a solution for it. I designed a board that it lets me to switch on/off since a remote computer one light (or another electrical component connected to the board) and it detect the manual state of the system, so it can change between remote mode and manual mode each time you touch the manual switch. It is really a electronical-remote conmutator.
You can find all the information about it schemes in another thread in this forum: http://arduino.cc/forum/index.php/topic,92963.30.html
It is in Spanish, but I think it is not difficult to understand the schemes.
Now, I have developed a new an industrial/commercial version of this solution. The previous version had one problem. It works fine, but it had a lot of possibilities to make a wrong connection. You can see some pictures about the new version at the end of the previous thread and it will be published too in the my new English thread: http://arduino.cc/forum/index.php/topic,116788.0.htmlhttp://arduino.cc/forum/index.php/topic,116788.0.html[/url]
I am going to open a eshop in a few days where I am going to sell production boards and prototype boards. If you are interested, please tell it to me. You will be able to find them at my web.