Great recycling idea. I read somewhere that some women were filling these bobbins and using them on theirsergers for small projects and didn't have enough spools of the same color. Don't know if it works or not though. When I bought my serger long ago, the sales lady said to always buy at least 4 spools of each color at a time, then everything matches. I have so much thread, I'll never be able to use it all. Wonder if I can use it for piecing quilts?