Are your electrical bills high from your AC this summer? What about trying some natural cooling strategies. Increasing ventilation and adding ceiling fans may give you needed relief. If you live in an older home you may already have natural cooling strategies already built-in into your home.
This is one strategy used on new homes: 
Read more about natural cooling strategies at: http://www.motherearthnews.com/green-homes/natural-cooling-zm0z11zphe.aspx
Green Real Estate Appraiser 