[Gothswitch]

I love a clothes peg zipper, as both dom and sub. The fear one sees in the eyes of the sub, or the dread felt as you wait for what you know is coming is exquisite.

However, I've been trying to think of a way to automate the "yanking" part. I can't think of an engineering item that really works in the way I would need it to - waiting for a time to build up the suspense, then making a short movement to pull the zipper.

Any ideas as to how I could create such a device?