Fed up of cold callers? Canvassers? People you just don't want to answer the door to? Give the door bell "key" to those you want to know have called (give different numbers to different people - Kids' friends get their own ring tone (bell tone routed through to their mobile phone). Gas meter reader gets their own code [may be based on your mobile number which you sometimes give nowadays])
-- Dub, Apr 16 2015

Well, it would provide some advance ID regarding who's at the door. Unknown persons would be confined to knocking.
-- normzone, Apr 16 2015


A recorded message saying "Warning ... warning ...incorrect code entry ... destruct sequence initiated .... " should have a suitably salutary effect on unwanted callers.
-- 8th of 7, Apr 17 2015


[8th of 7], I'm not sure that "destruct sequence initiated" would be very believable. Do YOU want a stranger entering the wrong code to YOUR front door, and then have YOUR door blow apart (enabling said stranger to enter house and steal stuff)?

I therefore suggest that "targeting sequence initiated" to be a superior and more believable message. You could even actually shoot stuff safely/scarily/possibly-even- legally, if the targeting system was used to determine where NOT to shoot.
-- Vernon, Apr 17 2015


Indeed ... "Defence system activated, weapons powering up, target aquisition sequence initiated .." would probably suit.
-- 8th of 7, Apr 17 2015


Please send me my code via facebook messenger, so I can pop in for a visit! [+]
-- xandram, Apr 17 2015


Certainly, [xandram]
-- Dub, Apr 17 2015


Couriers don't necessarily ring the bell as it is; I wouldn't want to give them any excuse.

...although, since in those cases I doubt they actually got to the door in any case, maybe a bell which took a photo of the visitor would be useful. It would identify burglars, too.
-- Loris, Apr 17 2015


Nice!
-- Dub, Apr 17 2015


// It would identify burglars, too //

So they'd have their own special code or something ?
-- 8th of 7, Apr 17 2015


Read the title + Read the rest later! :)
-- po, Apr 17 2015


<Goon Show>

"He opened the door in his pajamas. I said,'What a strange place to have a door'.".

</Goon Show>
-- 8th of 7, Apr 17 2015


The area the caller has to stand on to reach the bell should resemble very closely a large trap door. Hinges visible. Signage to read" Correct code MUST be used".
-- cudgel, Apr 17 2015


Super-duper idea dubs. Love it.
-- blissmiss, Apr 17 2015


" ... and with that, your Honour, we submit that the case of the People vs. [bigsleep] is proven beyond reasonable doubt ..."
-- 8th of 7, Apr 18 2015



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