I get about 6 or 7 a day and don't answer most of them. I quite often get a scam call in which they are saying my computer is infected with a virus and they need to get rid of it. (I believe they end up installing remote access software or perhaps spyware of some type).
Whenever I get these calls I keep them on the phone as long as I can and waste their time. They get veryyyy mad at the end and will often curse at me before hanging up

. The longer I waste their time, the less time they have to potentially be successful scamming someone that doesn't know any better.