let's start an army of "Silent Hello Robo-Answerers".
When you get a robo/telemarketer, punch through and set the phone down. Don't say or do anything until they hang up (or ma bell or ma Google hangs up for you).
Now imagine if hundreds of thousands of robocalls were answered that way. The people doing the robocalling would have to hire a huge staff to handle the "silent hellos". Their queues would be full and without handling each silent hello, they may lose the chance at the few people who fall for the call. It would kill the robo-call business.
And it is kinda fun to listen to them "hello, hello, are you there, can you hear me, hello..."
Spread the word, Help build an army of us who answer the calls, punch through and then be silent (or put by the radio). An army of "Silent Hello Robo-Answerers"
Update: It turns out that this technique is affecting robocallers and is why some systems now require a 2nd button press. It is an attempt to overcome those who start their answering machine message with the 1 DTMF tone. So maybe there is something we could do with AA where the message starts with a 1 DTMF tone.