In our household, there has been a noticeable decrease in scam telephone calls. In the past, we would get ten or more calls per day from the scam call centers in India (they use VOIP) and were quite easily identifiable by their Hindi accents and poor English skills. They were DIRECT calls to our land line. In the last few weeks, we only get recorded calls from "ATT" offering to "reduce down" our monthly bills. "PRESS 1 to be connected to claim your discount!" the recorded voice says. When you press one, you are then connected to the scam call center in India.
I always press one to talk to them. It costs them money to get that call connected to them over there in Kinsasha [I forget the real name of the town.] And I waste their time by pretending to go along with them, feeding them false information, and eventually practicing my Hindi skills on them (which they absolutely HATE.) There are days now where my phone doesn't ring at all. I've gotten scam calls down to maybe two or three calls a week. (We have caller ID on the television, the friends and legitimate calls are easy to spot. As are the scammers.)
My other "turn about is fair play" trick is to answer the scam calls thusly: "THANK YOU FOR CALLING BIBLE PHONE!!! OUR STUDY TODAY IS TAKEN FROM THE [turns Bible to random page] NINTH VERSE OF CHAPTER 8 OF THE BOOK OF ____________, LET US ATTEND [begins reading said section of Bible] ...." They can't hang up quick enough.
Once I had a listener, though! I used to cuss them out in Russian, but once I accidentally ripped on one of my Mom's friends in Russian. She took it in good humor, though. Nowadays, I think AT&T is cracking down on use of their phone lines for VOIP incoming from India. Thus, the scammers moved to the "having to press 1" to be connected to them ... and charging them for the call. At least that's my theory.