This is a fun thread - thanks for starting it, RedSIinPA. Oh, and thanks for letting us all gather here in your virtual watering hole, Peter.
Energy management systems and temperature controls have come a very long way in the last 15 years or so. The days of pneumatic controls are well and truly over, and we have clients these days with unified campus-wide controls networks that are web-based and cover HVAC systems, lighting controls, emergency generators, and even some plumbing. Even though we design the building systems and specify how they are all linked together, we don't often get to see a lot of that - just the submittals on it so we can make sure they've got the right idea on the sequence of operation, unless we also do commissioning on the project and end up getting a look at the final interface while putting the system through its paces - but it is some cool stuff. And I've been fortunate to work on some pretty interesting projects, including well-implemented control systems and some other impressive stuff.