Since this post is under the green living section I thought I might add this idea. Recycled blue jeans can be turned into house insulation. Here's a few links about it.
http://www.environmentalhomecenter. ... &ProdCode=COTTON_INSULATION#more
http://www.inhabitat.com/2006/11/26 ... lue-jean-insulation-by-bonded-logic/
The most effective is spray foam insulation. It is a vapor barrier as well as a thermal barrier, so it does double duty, too. It is expensive, though, and should be professionally installed. Call some contractors in your area to get some quotes. Also ask for the 'payback' (how many years before you save enough in your heating and cooling to pay yourself back).
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