Hey Cofty, I was being hassled a few years ago by these Indian scumbags, so I finally decided to string them along for as long as possible - to waste their time! I kept asking them to repeat their instructions (to get remote access to my PC) and then finally told them that I couldn't continue any more with his requests.
When he asked me "Why not?", I told him that the men in white coats had come and taken away my laptop! I then laughed when he used some expletives to describe me.
Downside: these pond-life started 'phoning me during the night, so I had to disconnect every evening for some time.