Although the large tax credit has expired, there is still a tax credit available for the consumer. For new Energy Star compliant windows you may qualify. You dont have to replace all your windows and you dont even have to replace an existing window, you can make a new opening in a wall and place a compliant window there. They do have to be placed in service by December 31, 2011 to qualify. Windows are capped at a maximum credit of 200 dollars and it must be your primary residence as in previous years.