For those of you with furnaces

Two notes now that we're in the cold part of the year.

• Replace your furnace filter. It's probably filthy.
  
• Rebalance your vent registers. Are some of your rooms colder than others? Open the registers in those rooms all the way and close the registers in the rooms that are warmer (not completely—just a little). Even if you had these properly configured last year, they often get bumped out of shape over time.
  

Enjoy.