I thought a mug warmer would be a fun, and useful, item to crochet. I used this pattern from JoAnn's, with slight tweaking for yarn weight and mug size.
This was my piece before connecting the ends. It fit snug around the glass that I had with me at work (yes, because I crochet on my lunch break). With a little stretching, the piece fit much better.
Using the tails, I weaved the two sides together at the top and bottom. The last step is attaching a button to one side to unite the piece underneath the mug handle.
This is another warmer I made with a dip for the mouth; made using slip stitches.