For those in apartments or rentals without control over the heating, consider leaving the hot and cold water taps dripping. If your pipes freeze, unscrupulous landlords may blame you for burst pipes.

My landlord put my bathroom pipes just inside an exterior, uninsulated wall and was upset that they froze, burst and damaged the two floors below me. Fortunately, he ended up being pretty cool about it. He replaced those pipes with expandable pipes, but put them back on the exterior wall.......without insulation. They have frozen since, about three times, but fortunately, no permanent damage.