Coleen, the owner of the Dilworth Coffee House, where my knitting group, The Knit Nuts meets asked us to knit or crochet cozies which she could offer her customers. The cozy would replace the cardboard one and fits well the paper cups.
Here's a flat view of the cozy. The cozy wraps around the cup and is fastened with a button. This cozy was crocheted using a diagonal shell pattern.
The Cozy fits small, medium and large cups.