Last night I was thinking about ways to improve upon u-locks. Even though they offer the highest level of security available, they can still be defeated, as this post demonstrated.

So it occurred to me: Imagine a U-lock that had wires embedded in the shackle, such that when the lock is closed, a circuit is completed. If a thief tries to cut through the shackle, the wires are compromised, the circuit is broken, and that sends an alarm to your key, notifying you that somebody is cutting your lock. Seems like the next generation, doesn't it?

What ideas do you think could be implemented to improve bicycle locks?