Staying warm. In the winter, I used to stay warm by turning up the thermostat. Then I discovered (via HN) the Low-Tech Magazine article, "Insulation: first the body, then the home." [0] The article argued that it's much more efficient to focus on heating yourself rather than your whole living space. I invested in high-quality wool clothes that I wear in layers and warm slippers. Now, I keep my home about 5 degrees F…
Add moisture to the air also as it conducts heat better and the same temperature will "feel" warmer. (especially important in some climates more than others)
Also, I'm not sure if there is an easy way to actually increase humidity without reducing the temperature. From my experience, increasing humidity while keeping the overall temperature at the same time requires additional energy.
Also, less humid air may allow you to actually wear less cloths as it is more difficult for the air to get energy off your body.