I've always been fascinated by home automation and have been incorporating it into my residence ever since I've owned my first home 20 years ago. When I first started, I used X-10 and Xtension software. At first I just automated a couple of lamps, but it grew piece by piece. When I moved into my new house in 2004, I had originally planned on continuing with X-10, unfortunately X-10 is very susceptible to noise and I struggled to find the time to track down the sources. So I migrated over to Insteon. While I wanted to continue using Xtension due to the dedication of the authors (Michael and James are a great and responsive couple of guys), they were unwilling to support Insteon due to the cost/complexibilty/immaturity of the interface, so I transitioned to Indigo. In the meantime, Xtension is now supporting ZWave and has added a lot of capability since I switched away. I'm currently happy with my extensive Insteon setup, but if you are starting from scratch, I would carefully consider both as I believe they each have their strong points. I'm not going to directly compare them as I haven't actually used Xtension in years and thus have no basis for an objective comparison, but as I do follow their mailing list I can say that there is a lot of hidden capability and some real experts at true do-it-yourself home automation.
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