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The reason there's no 'good' home automation products is because there's not enough demand, pure and simple. At the end of the day, HA is 99% bling and maybe 1% utility.

Agreed. The place where building automation is underused, though, is in places that have meeting rooms - schools, universities, churches, offices, and hotels. Meeting rooms need the full set of sensors for HVAC control - movement, heat, C02, CO, temperature, and humidity. These are in place in many buildings today, but not in enough of them.

Meeting rooms have the property that the people load changes suddenly. A completely empty room can have its lights turned out, or at least very low, and the air change rate can be cut very low. When people enter a room, the lights come up, dampers open, and blower speeds increase. The CO2 measurement is an indicator of people load; when CO2 goes up, blower speeds have to go up to increase the air change rate. CO content indicates smokers, which means more air has to be drawn from the outside. And, of course, the system is measuring these parameters for outside air, so outside air can be used to heat, cool, humidify, or dehumidify, as required.

This alone makes meeting rooms much more pleasant, while cutting energy use. But there's no "bling factor" to this. It's invisible to almost everyone.

The next time you enter a conference room with a group in a modern building, listen for blowers winding up to speed and the whir of motors moving dampers. Somewhere, a microcontroller and network are quietly doing their job.

Trane manufactures packaged units. The "HVAC system in a box" unit has existed for decades. In fact, I have one on my house (best money I ever spent ... got that noisy blower outside.) Granted, it's not in a sea-freight container, but it's about the same overhead to connect to your server-cluster-in-a-box. What's next? Cubicle in a box?

...they have attempted to do like they do in surgery tent in Iraq and create a positive air flow?

I don't know, but it might not be a good idea. According to http://healthandenergy.com/suggested_indoor_air_pressure.htm,

Moisture condensation and damage can occur below the roofs and within outer walls of heated buildings if indoor air pressure is significantly greater than outdoor air pressure.

Of course, the next section of this page appears to contradict this....

http://www.trane.com/commercial/library/vol31_2/index.asp#control has more on this. Summary: It's complicated, man.

I asked about maintaining a positive pressure differential when we had an ERV installed (for reasons similar to those suggested by the PP); the technician indicated that while a nice theory, it could cause the ERV to ice up. They had been instructed to create a slightly negative pressure differential for this reason.

So my modern, plastic sealed house has slightly negative pressure relative to the outside. Several years and counting, and no negative side effects as far as I can tell.

Oh, and that's in Ottawa: Summer highs in the 40s, and very humid, winter lows in the -30s, and very dry. Nothing too extreme....

Something you can do with new buildings and homes is to put in a "Zoning System"

companies like Trane will charge you a fucking arm and a leg for it, but I read a DIY article somewhere.

Basically, you install various 'dampers' in the ducting that are controlled from a central thermostat. The fun part, is that there are temperature sensors in each zone, so the thermostat can intelligently shunt hot/cold air to the areas that need it.

As I said, the big commercial suppliers will rip you off on the price of the control system & they'll give you a relatively limited solution compared to something you can do yourself.

This works wonders in structures that have uneven temperatures because of solar heating or being underground. Unfortunately, it's prohibitively expensive to try and retrofit this into a prexisting home/building.

P.S. You want the failure mode to default to 'open' and not closed.

I switched to Linux becauz a Trane was too noisy.

Like one of these?
Or this?
How about one of these?

Why is this interesting? It has NOTHING to do with the topic at hand. Here...let me be interesting:
Install a better air conditioner. Like a Trane or something.

Real Men measure their air conditioners in tons.