There are lots of little things that can be done to save energy in your home. All the little things add up over time, or cost you over time. Suppose you can cut down your homes electrical usage by one kilowatt an hour, over the course of a year that would be over 8700 kilowatts that you didn't have to buy. At 10 cents a Kwh, which is cheap for most areas, that would be a savings of over $800, that's over $50 per month savings.
Compact florescent light bulbs cost a little more upfront but will save more in electricity costs over their life. It is not even necessary to replace all the bulbs at once, simply replace them as needed, which will also help spread out the upfront cost of switching to them.
Use appliances that heat up as continuously as possible. Using a clothes line is more energy efficient than using a clothes dryer, but if you use the clothes dryer try to use it as continuously as possible. Use the residual heat from one load to the next, don't let it cool down. The same goes for the oven, once it's heated up for baking dinner, go ahead, bake those cookies right after you take dinner out. Then you'll have fresh cookies for dessert.
Change your filters. Change the filter in the HVAC unit, not only will this save energy but it will help keep the air cleaner in the house. Change the sediment filter in your water line, if you have one. Change the filter in for the ice maker and water in the refrigerator. Changing filters can be a catch-22, changing them too often will cost more than any savings from better energy efficiency. Examine your filters and try to find a good balance of dirt filtered against the cost of the filter.
Break out the vacuum cleaner to make the refrigerator run more efficiently. The coils on back of the refrigerator need to be kept clean for the compressor to run efficiently. Use the vacuum to clean out whatever dust and dirt accumulate on the coils. This can be quite significant, especially if there are pets in the house. Check the coils on any freezer or air conditioning units to help them run better also.
Doing some routine maintenance and changing a couple habits to can a long way towards making your house run more efficiently. There really should be to much of a time investment if you do these things routinely.