Switch your ceiling fan to run clockwise on low speed in winter
Added
Most ceiling fans have a direction switch on the motor housing. In winter, set it to clockwise and run the fan on low to push warm air from the ceiling back down into the room, and turn the fan off when nobody is in the room. Switch back to counterclockwise in summer. Turn the fan off and let it stop before flipping the switch.
The result
Result: ENERGY STAR: clockwise at low speed makes a gentle updraft that forces warm air near the ceiling down into the room; adjusting your thermostat along with it can add energy savings.
Source
ENERGY STAR (Ceiling fan installation and usage tips) (opens the original source in a new tab). Check it for the latest numbers before you act.