I rewind the thread to a bobbin to fit my sewing machine and use it to sew on the binding. I, also, topstitch the binding down with my sewing machine, so I get two rounds out of it. When I found I was running out of bobbins, I went to Ebay and ordered a box of 100 L bobbins for about $30. This has helped a lot. Sometimes I use the bobbins for piecing. I don't throw away thread unless it is a very small amount.