If you lose a key it is quite easy to get a replacement, providing you have a replacement to begin with, by going to a "key cutting shop". [1]
However, most people have a key that doesn't open any lock, or at least, none they have access to. They have in effect lost the lock.

To make use of those wasted keys, I propose a complement to the key cutting service; the lock cutting service. Essentially you would take along your random spare keys, and get new ones made in the form-factor you desired.
Want a universal key which opens your house, safe, locker, car and/or bike-lock? You need this service.[2]
Got a rusty old antique key you like the style of, or one with sentimental value? You need this service.
Had a set of personalised keys made but moving house? You need this service.

Using computers, laser scanning, and automated precision cutting machines, I don't think this would be practically all that difficult.

[1] For some reason these shops universally repair shoes as well. This has never been satisfactorily explained.
[2] If you are worried that this is insecure, bear in mind that most people carry all their keys linked together anyway. Just get your bike-lock cut to fit a five-lever mortice key, rather than a house-lock from a bike-lock-key.
-- Loris, May 02 2007

re: [1] You could create extra trade for these businesses if you invented lockable shoes, perhaps under the premise that they don't get stolen at the gym.
-- marklar, May 02 2007


You can buy pin sets for some (maybe most) good cylinder locks, allowing you to rebuild the cylinder to match a given key - this is often important if, for instance, you want one key to open many doors. Of course, the key has to be of the right type (I mean, the right section and length).
-- MaxwellBuchanan, May 02 2007


Any good locksmith can already do this... I've had it done a few times
-- xenzag, May 02 2007


Following on from the recent 'In-store Psychic' idea, you could have one that told you where the lock was, just by rubbing the key (beware of Yuri Geller though, he'll bend it)
-- marklar, May 02 2007


//This has never been satisfactorily explained.// It's something to do with those whirly grindy things.
-- zen_tom, May 02 2007


I have six keys on my key-chain. Four of them I never use, and I've even forgotten what they go to. Yet, it somehow seems wrong to just have just two keys. I would feel...impoverished.
-- ldischler, May 02 2007


//Yet, it somehow seems wrong to just have just two keys. I would feel...impoverished.//

Letting go of your keys is the first step to attaining inner peace. Finding others' keys is the first step to obtaining their stuff.
-- Noexit, May 02 2007


In my area, shoe repair stores and locksmith stores are separate. Locksmiths can also make doorknobs or other locks to fit different keys. A certain amount of correct matching-up is necessary though.
-- ye_river_xiv, May 03 2007



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