This one basically involves a screwdriver. But it's still really easy to do, and the payoff can be huge.According the federal government, you can save as much as 10 percent a year on your heating/cooling bills by turning back your thermostat while you're at work and/or asleep.The simple way to do this is to install a battery-powered programmable thermostat. Just turn the power off to where your old dial thermostat is located, unhook it and install the new one. It's just a few wires off, a few wires on. Not a big deal all.When the new one is online, you can program it to any temperature for any time of the day or week. Wintertime and you're at work? No need to heat an empty house. Back off a few degrees. Summertime and you're at the beach for the day? Have the temp go up automatically. No need to keep it cool if you're not there.You can also use the manual override without affecting the rest of the daily or weekly program. The other person in the house, for example, might want it set on 68 instead of 63. She's sick of winter, and wants a break for a few hours! No problem. But since you bought it -- and installed it-- you reserve the right to hike it down to 59 the second her eyes shut for the evening.It's only fair!