Cellphones which use SIM cards, such as those used by T-Mobile and at&t, are superior to non-SIM phones, such as those used by Sprint and Verizon, for a number of reasons, which I won't go into here because I'll forget the idea by the time I'm done if I do. One major drawback, however, is security. If somebody steals your phone, all they have to do is take your SIM out and put their own in and they've got a new phone. Even if you report your phone stolen, very few, if any, carriers will hotline (lock down) the IMEI (a phone's unique serial number) to prevent it from being used on another account. Let me assure you, this is a policy, not a limitation, because they do it for phones that are stolen before they get sold at a store, thus protecting their own interests, but that's another issue that I'll let someone else fight out in court. All they do is deactivate your SIM, which is very easy to remove and replace.

So my idea is to have a tiny, 3- wheel combination lock built into the phone that physically prevents the back of the phone's casing from being removed without permanently damaging the internal circuitry. The lock can be very small, and need not add much weight or bulk. Think along the lines of those tiny suitcase locks. In the event that you need to replace the SIM or battery and forget the combination, simply take it to your local carrier's store, provide photo ID to prove that the IMEI is registered to you, and they can open it with a special key, like the TSA uses to open approved luggage locks. To prevent unscrupulous store sales agents from making a copy of the key or stealing the key, it would be mounted in a machine, like a drill press, that is bolted to the countertop.
-- 21 Quest, Aug 18 2009

Video: paper clip vs. Master Lock #175 http://www.youtube....watch?v=jCz3_ladHNM
Unlike pin tumbler lock picking, you don't lift the pins, you just get past the wheels to poke at a little lever and shift it. (Obviously, this depends on the exact model of lock.) [jutta, Aug 19 2009]

Video: paper clip vs. luggage-style lock http://www.youtube....watch?v=Si9wZRSfLBg
Huh! I don't really know what's going on here, other than "these locks are really crappy". [jutta, Aug 19 2009]

It's standard practice (in the UK) for mobile phone operators to lock out the IMEI of a stolen mobile phone.
-- hippo, Aug 19 2009


//Think along the lines of those tiny suitcase locks//
You mean the ones that then got twice as big because Homeland Security demanded they be fitted with a pin tumbler mechanism?
What [hippo] said.
-- coprocephalous, Aug 19 2009


Sorry, I learned to pick those suitcase locks with a paperclip when I was very young and I claim no skill in this area, it was just that easy. (-)
-- MisterQED, Aug 19 2009


I'm sick of everything being digital. I would like this [+]
-- xenzag, Aug 19 2009


//I'm sick of everything being digital//
I dunno - I don't really like analogue locks.
-- coprocephalous, Aug 19 2009


QED, I'm interested to know how you learned to pick a combination lock with a paperclip. Where do you insert the clip, exactly?
-- 21 Quest, Aug 19 2009


In your ear. Where else ?
-- 8th of 7, Aug 19 2009


I'm assuming you meant the slot into which the TSA master key would be inserted. The solution to that is simply a higher-quality lock.
-- 21 Quest, Aug 19 2009



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