I had one included in a home security package, and the one useful thing I found to do with it is automate it to turn on and increase brightness slowly in my bedside lamp before my alarm would ring. That was a gentle way to wake up each morning, and much cheaper than doing the same with automated blinds.
The second best use I could think of was automatically controlling outdoor lights in the evening, given that my front lights are on a different floor than my main living area. But I never really bothered with that.