I've looked around a bit, and it seems that no vendors are making wallbox dimmers and other devices that are designed for retrofit installation. It appears that years ago Leviton made something, but they dropped the product.

I'm guessing that the LonWorks powerline technology back then did not work very well. It also appears that last year Echelon released a new powerline technology, and on their website they have a number of promotional plugs for how this will revolutionize home automation.

However, I can't seem to find even a single vendor that is making anything based on this technology that is designed for retrofit. Am I missing something? Are these products around the corner? Clearly, at least to me, using LonWorks is the way to go, if only I could find some products.

 

About 5 years ago I worked for a company that had built powerline products but went out of business. The company assets with regard to powerline lighting controls had been sold to a company in California. Please let me know if you are interested in the details.

Aside from that, there was a company called HalenSmart that went out of business about 4 years ago.