I sat and read all of these wonderful comments, and I guess I am not a purist. I use anything I can get my hands on, even (horror of horrors) not 100% cotton. Using old clothes gives me a sense of thriftiness and some of my favorite quilts have a WIDE assortment of types of fabrics. I have found after they are quilted, then washed, all of the fabrics seem to just go together. The blends get just as soft as the cottons, and as a matter of fact they don't "age" as much (whitening of the fabric). I guess I am lucky because no quilt police live by me!!!!