A small bit of electronics in between your phone and the wall .. that reads when an incoming call is happening. Before it starts to ring the actual telephone, the machine waits for 2 more 'typing tones' to be heard. If it doesn't hear the extra 2 tones within 30 seconds it hangs up. Now the machine can be programmed to do different things depending on which additional numbers were typed in.

So if your actual telephone number is 555 45555 you actually give out the following numbers:

You give to friend #1 555 4555501 you give to friend #2 555 4555502 you give to company #1 555 4555503 you give your psycho-girlfriend 555 4555504 your boss 555 4555505

So for exactly the same price as 1 line, you have 99 phone lines coming into your house (just 1 at a time). And the machine can start doing automatic functionality based on who is calling (because you know who you gave which of your 99 numbers to).

Now once your dealings with company #1 are over and you've bought your double-glazing, set your electronics box to hang-up on all calls coming in to that number. So - no more telesales from that company. No more even if they sell your number to another company (which happens a lot).

You know which of your friends is calling because of the phone ring-tone without giving any more money to the phone company. Your psycho-girlfriend who keeps trying to call her after you've split up? Just tell the equipment to 'hangup' if it hears the '04' tone. It makes no difference if she 'hides her number' from your caller-id. The very fact she is the only persona you gave the '04' ending number to means she can't get to you.

Your boss calls .. even if he has called from a call-box so caller id won't work .. you know because of the ringing tone you assigned to '05' it's time to avoid the 'Hiya freak-head' greeting you normally use, for a more responsible greeting.

Give your daughter 555 4555506. If the machine gets incoming ringing for this number it auto-calls the number back whilst ringing your phone. A way in emergency she can make reverse-charge calls.

All this without giving the phone company an extra penny ...
-- britboy, Aug 11 2004

If this catches on, your psycho-girlfriend will know to try 01, 02, 03, etc. until she reaches you. To prevent this you will need long codes, and I hope none of your freinds are as bad at remembering numbers as I am.
-- GutPunchLullabies, Aug 11 2004


How much does caller id cost these days?
-- yabba do yabba dabba, Aug 11 2004


How do you know if she's psycho until you break up?
Oh, hi! Listen, I got a new phone number. Yes, from now on it's 555-555504. Please forget any previous numbers I've already had. What? No, it's not a psycho line, honest! I'm giving all my friends this same number. Huh? No. I just don't...feel like using the old one anymore. Of course not, please, stop asking. I swear, even my mother isn't calling the old number anymore. Yes, 555-555504, that's right. Feel free to call me anytime. *click*
-- phundug, Aug 11 2004


This idea assumes that the telco switches will pass the additional tones to be ”heard” by your proposed device. I'm fairly sure that they don't. The switch, once the appropriate number of digits are pressed, immediately acts on those digits and discards the overflow.

Even if the caller waits until the ring tones begin and then types in the extra digits, the digits will be lost to the ether as there is not yet a connection to the target phone.

If the proposed device instead acted like an answering machine and answered the call and then listened for a pair of tones to route the call, well . . . then it would work but that's already been invented.
-- bristolz, Aug 11 2004


If your phone is going to hang up on a call to the published number, why not just have an unlisted number? I know the cost differs by region, but everywhere I've lived it's pretty reasonable. No special machine, and especially no hassle with a different email to everyone.
-- bpilot, Aug 12 2004


There may be complications for people outside the U.S. (aren't there always?), but to the extent of what you've described, I believe it could all be done with asterisk. Now, since I don't currently have any landline, that's my excuse for not experimenting with Asterisk personally, but I lived in a house in Seattle where my pal (and landlord) obsessive electronic / computer genius Brian had Asterisk going, and it was certainly possible to require -- as in fact this system did -- an additional input of digits to reach someone, as in "Press 1 for Tim, Press 2 for Christine," etc. I'm sure you could suppress the audible menu altogether, leave 'em guessing. Hmm. Now I'm getting tempted to get a Vonage line in order to play with this a bit. Oh, and at our house, while I'm not sure if this was a default setting or something Brian put it for his own amusement, but it was "Press 4 to hear monkeys." And indeed, there were monkey sounds to listen to.
-- yhtomit, Jan 21 2006



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