I also just had a thought about a possible auto-lacing device. If anybody knows of a way to get a very small motor that can turn a gear a 1/4 turn and back and lock in both positions with the push of a button, I've got a design that could work very well.
I'm not sure if they exist, but some sort of worm gear stepper motor might fit the bill.
I'm no expert though, I just play one on the internet.
-Nick