Actually, if you have the time, hold the caller on the line as long as possible. But don't do anything on your computer.
I kept two of them on a call for about an hour this year - I told them they were crooks, and we discussed everything from how his mother would feel about his being a criminal, to how his actions hurt people, to a phony discussion with him lying about where he was located to his asking me to help him get an honest job instead. I even said why I was keeping the call going, to keep him from being able to scam someone while he was on the phone, and he took the bait saying he wouldn't hang up, and didn't for a long time. It's a known scam.
