Cool, TRH. I like the airbrushing.
Chris, I'm bad - I didn't end up making one of these. I started thinking the center of this design really needed support, like this one by dextannery. or it would be hard to close it without damaging the glasses.
So instead I made several based on Norman Cahn's design:
You should look through dextannery's shop. There are some pretty cool ideas for covering large car keys.