I just happened to come across an interesting little trick the other day to stop automated telemarketers. For the past few months, my land line has been getting a fairly steady amount of these calls. Sometimes I pick up the phone, say hello, then listen during that awkward two seconds of silence before the system realizes “oops, I guess I should play the recording now”. Either that, or the recording starts talking to my answering machine.
To my surprise, it looks like there is a simple “hack” to stop these calls in their tracks,
http://home.flash.net/~carlton2/telemark.htm (original link is dead, here is an archived copy)
Basically, if you’ve ever dialed a number that’s been disconnected, you’ll hear a series of three tones that go “doo…dah…dee”. Now, all you have to do is play those tones so it will be the first audible sound that the automated telemarketer picks up.
As explained on the website, the automated telemarketer system will be tricked into disconnecting because of hearing the three “out of service” tones, and then will proceed to remove your phone number from their list of active numbers. That means you won’t get another call from the particular company, and they won’t sell your number to any other companies because it will be seen as an invalid disconnected number.