Bike locks have to be very strong to resist clever thieves. However, the stronger they are, the more unwieldy they tend to be. Three Chilean students puzzled this out and created a very special bike which converts from an ordinary bicycle to bike lock with just a few hand movements and in only 20 seconds. Any potential thief would break his prize trying to unlock it, so he had better keep his hands off it. An additional lock is not necessary.
The unstealable bike is still in the prototype stage. The three inventors are searching for sponsors for future serial production via their website.