
If all goes well, this summer I'll be building a new house. I've owned a few houses before, some of them built in the 1920s and 30s, and full of all the charm and quirks of an old house, and a couple that were pretty new, with the lack of craftsmanship and imagination that's typical in most new construction in the USA today. But this time I'm building a custom home, just to my specifications, so I can have whatever features I want, limited only by my imagination (and budget). I'd like to integrate some home automation features into the house, and include wiring for future expansion.
You can easily hook up your lights to your Parallel Port using a solid-state relay. That way you could control it software-based (hell, that's how I do it).
Of course the parallel port is only an option for one room. When doing multiple rooms (or even an entire house) it's probably cheaper and easier to you just look at some cheap domotica-systems.