Smart Homes

"Traditionally, heating, ventilation and air conditioning (HVAC) systems operate independently of each other... conventional environmental control systems typically waste 50 percent of a building's power. Much of this inefficiency is because each element, such as an office building's water chiller or heating unit, relies on a single control that measures only one variable."
--you can read the full article here

If large building can be made to make use of intelligent systems, would it be possible to do something similar with a home?
There are a variety of suggested uses in large buildings - such as HVAC control, personelle access, lighting adjustment based on available sunlight, and so on - though only some of them would apply to a home.

What could we do other than reacting to changes in temperature (ie. having a thermostat)?
One thing I've noticed recently is that I occasionally have to go outside to get a breath of fresh air after being inside for a while, and I regularly have windows and doors open to let air circulate. The change is noticable to me, like when you're dehydrated and take that first drink of water. So I'd suggest working on improving ventilation, whether or not such improvements take the form of a smart system.