My grandparents have cloth coasters that we put hot mugs on. They work fairly well as far as not sticking to the cup and beautifully as far as protecting the furniture (especially when we use two at the same time). I have a yarn crochet Granny square that I now use as a coaster for my teapot, and it works fairly nicely. So I think maybe if one can crochet or sew, one can make their own. Oh, and I think for Adagio coasters, maybe cork or cloth?