...and many would...but I like my environment to be set-up right. In particular, I'm pretty fussy about being at the right temperature. Yet inadequate control plagues our office and particularly home heating systems, wasting huge amounts of energy and making us uncomfortable into the bargain.
This came up in specing the HVAC system for our new office. Optimising zones v. heat recovery v. control sophistication is pretty complex and more control can be quite costly. Moreover, just modelling each room to answer questions like "will we always be able to get it to 21C within 1 hour" is surprisingly fraught. What outside temperatures to assume? How insulating are the room's walls, floor and ceiling? What are their heat capacities? How many people will be there?
(I can't help noticing this would be a great computerbasedmath.org module. It's exactly the sort of real-life maths question that today's curricula don't equip students well for and for which learning intricacies of hand-calculating won't help you).
Next step: see whether we can get to the system's API and use Mathematica to make a nice interface to it.
For the home, there are an increasing range of retrofit, wireless solutions for traditional wet central heating systems that have only a few years of payback. I've for some time had a Honeywell CM-ZONE and now an EVOHOME I put in. One of the worst marketed piece of tech, it's a pretty nice system that most plumbers don't know about.