The mastercuff at Cavern really got me thinking about hand cuffs and locking bikes. I asked a couple of people who suggested these and I was wondering if anyone would be interested in a pair so we can bundle our order. I wouldn't suggest using them alone to lock a bike but to keep your wheels attached to your frame and using a mini U to lock the frame they might be perfect. They are also hinged instead of using a chain so they are much harder to bypass.
Just a thought.