My family gets about 4 phone calls from telemarketers each day. Our typical
routine is to hang up as soon as we hear the recording tell us that we are
"$10,000 into credit card debt" or our "factory car warranty has expired".
My new approach is to simply put the phone on the counter and let nature
take its course. I'm no telco genius, but this probably ties up
one of their phone lines for the duration of the recording. If I get really
lucky, it will eventually patch a person through whereupon: "Hello ... hello ..." and they'll get nothing but silence. Ah, sweet justice!