The answer is --- it depends. That's because it really depends on a lot! It depends on where you live and how much wind you have in that area. It depends not only on the initial cost, but also on what rebates might be available from state or local governments. And, even if the answers to the first two questions are positive, it also depends on whether the local government will allow you to have a wind generator on your property without triggering any crazy zoning variances that can cost thousands to resolve.That all said, I did see a wind generator last May at the 2010 National Hardware Show that was literally a showstopper. It is called the Honeywell Windtronic Generator and it costs around $6,500 and can easily be added to virtually any roof structure.There's a very handy calculator that Windtronics created that'll help you determine the true cost of the unit as well as the ROI at www.windknowledge.com. I used it and was surprised to learn that my total out-of-pocket would be just $1,300 and it would start paying for itself in less than two years!