I recently made a few sets of these to sell at our exhibition here in Spain. They sold like hot cakes! I found a different tutorial which called the ones made on the diagonal "Glass slippers". You can pop the stem of a wine glass inside so that the glass is permanently connected to its coaster. Brilliant for parties, particularly if you make each with different fabrics so that each person recognises their own drink. I just use scraps of batting. They absorb any moisture when you have ice in a drink and are completely washable.