A. The burglar block key you placed in an obvious place under the door mat will be used first to try and fail to open the front door. The burglar blocker key is designed to break off in the lock. Hopefully the perp will freak out enough for them to leave and try the building next door instead. [1]

B. Burglars often break in through a window, get a haul larger then the window, and need to open the door with the spare key under the doormat to get the haul out.

The owner has installed a double cylinder deadbolt but the burglar finds the key under the mat or the other common places where burglars look for spare keys. The easily found burglar blocker key is designed to break off inside the inner door lock too. The burglar figures it might take longer than 8 - 12 minutes they usually spend onsite in the cold Canadian winter and takes off to have a beer to calm their nerves, eh? [2]

Downside: Though the haul will be less or none, you will have dig the broken key out, unless the enclosed magnet will not pull it out. Practice pulling out broken keys before you really have to -- It's a good life hack to know anyway. [3]

Disclaimers: As you know, we get so &8%! many ideas popping into our head while we are laying in bed, and have to jump up to get the PC so we can get into HB before the thought slips our mind, there just ain't enough time to proofread in depth.

I still have several pages of other ideas to enter that I haven't because the $&^! spelling Nazis will attack; I'm not writing a thesis here. My glasses are still on the bed. I still like to like to link search engines too. Leave me alone :~|>
-- Sunstone, Jun 02 2016

(?) [1] Worst places to hide your keys https://duckduckgo....de+your+keys&ia=web
[Sunstone, Jun 02 2016]

[2] Average burglar stay time https://duckduckgo....o+12+minutes&ia=web
It's a good life hack to know anyway [Sunstone, Jun 02 2016]

[3] Practice removing broken keys https://duckduckgo....rom+locks&ia=videos
[Sunstone, Jun 02 2016]

[4] For you spelling/grammer trolls out there https://www.youtube...watch?v=-pi1JKNlTyU
Enuf said [Sunstone, Jun 02 2016]

This makes me think that maybe the best place to hide your key is under the doormat/under a flowerpot of the house next door
-- hippo, Jun 02 2016


The best place to hide your spare key is under your rattlesnake.
-- 8th of 7, Jun 02 2016


Trying to remove a broken key can be infuriating. Especially so, when one owns many tools which could assist in the removal, all located _inside_ the locked building.

Thankfully I was able to enter via a window on that occasion.

Perhaps the breakable key could be made of gallium, so pouring hot water into the lock would melt it.
-- mitxela, Jun 02 2016


This is a good idea except for the fact that it won't work. Why leave any sort of a dummy or jamming key where it can be found?

If the burglar finds it and tries it, the only result is inconvenience to you. If the burglar is still intent on burgling, she will do exactly what most burglars do, which is break or pry a window or door that's out of sight.

If you want to prevent the burglar from exiting with stolen goods through your front door, then just fit a good deadbolt, leave it locked when you go out, and don't leave any kind of spare key where it can be found.
-- MaxwellBuchanan, Jun 02 2016


//Leave me alone :~|>// Why bother posting anything here if you want to be left alone?
-- xenzag, Jun 02 2016


// we can get into HB before the thought slips our mind //

Love the first person plural ... sounds like you're ripe for Assimilation. Of course, never forgetting things is one of the multitudinous benefits of being part of an Evil Collective Hegemonising Swarm ...

// the $&^! spelling Nazis will attack; //

Sp. "#%$? spelling Nazis".

You need to worry about the Grammar Commandos, and the Syntax Guerillas too ....

// My glasses are still on the bed. //

Glasses ? Bad place to leave them, too easy to spill stuff. Better to get one of those wide-base mugs, and keep it on the nightstand.

// Leave me alone :~|> //

No, shan't.
-- 8th of 7, Jun 02 2016


If you're going to have a special key under the doormat, why not make it "really special". If it is used, it doesn't unlock the door (or break off in the hole). It does however set off the audible alarm, a few camera flashes, etc.
-- scad mientist, Jun 02 2016


It's just another misspelling - should read " leave me a loan "
-- normzone, Jun 02 2016


If the key shaft is hollow, and filled with cyanogen under pressure, there's a chance that the perpetrator might end up very ill, or even better, dead.
-- 8th of 7, Jun 06 2016



random, halfbakery