Yes a thermostat. I am not officially a hippie geek.
Before December 25th, we had a programmable thermostat that was never really worked. We should earn an A for effort, but the programming was hard to set up and once the batteries quit so did we. For the last several years we just would turn it up or down when necessary, so basically our house stayed the same temperature, not good for energy efficiency.
Now we have a Nest and we are very aware of our energy usage, the temperature in the house, the humidity in the house, and how to be the most efficient.
I LOVE IT! I honestly never thought I could get excited over a thermostat, but I am.
Our nest tracks our energy usage and we try and earn leaves:
So last year's experiment was homemade laundry detergent, this year, energy efficiency in heating and cooling. Yes, I am yet one more step closer to becoming a hippie or maybe an just an energy nazi.