Through December 31st 2007, if you purchase specific qualifying energy-efficient items for your home, you can save hundreds of dollars via federal tax rebates.
Water heaters 80% efficient or greater (tankless) – $300
Furnaces 95% efficient or greater – $150
Air Conditioners 14 SEER or greater – $300
Insulation – 10% of cost, up to $500
Windows – 10% of cost, up to $200
There are many other items that qualify, for more information and a complete list, please visit EnergyStar.gov’s page for more information.