Programming allows the user to take advantage of peak heating and cooling times and thus reduce electricity use and utility bills. And the user doesn't need to remember to change thermostat settings each time the building is entered or left. Consider replacing existing bulbs with CFLs, which are available at all major hardware stores and home centers. Also remember to turn lights off when they are not in use. For a small cost you get a high return.
Insulated drapes keep the interior cool in summer and reduce heat loss in winter.
Many companies have ride-sharing programs as do many local governments and communities. Optimum temperature should be between 100 and 130 degrees. Dust in the filter reduces air flow, making a furnace or air conditioner work harder and longer.