The last one I spoke to was on a slow day so I let him ramble on for a bit, he was a nice Indian Boy surprisingly called "John Smith", then I said stop a minute John, this is a scam, you know it is a scam, I know it is a scam how do you live with yourself you low life? He then totally lost it shouting that I was wasting his time and as I put the phone down he called me a F***ing C*** and a B******. The lack of good manners in one so young is quite shocking.
Previously I have just told them they can't be very good at their job because I haven't got a computer, and suggested a new career in sewer maintenance. ("It's far less stressful and you meet people and things just like you").