yes, I have a lot of stray blocks that I make up into potholders when the mood strikes me. Some of the smaller blocks need a border added to make them a usable size. They are great for practicing with new stitches or FMQ.
I get the batting with the shiny heat proof lining.. can't think of the name right now. And I use at least two layers of in the pot holder.. one layer is NOT good. Trust me on that!