there is a person on twitch.tv that scam baits these guys. he will call them back and pretend to be an old lady and just waste their time. it's hilarious and very enlightening to see the tactics these guys use.
his old lady character is both the best and worst because while you are watching and it's funny, its also kind of sad that you get to see the tactics these scumbags use to trick little old ladies into giving them their life savings
https://www.twitch.tv/kitboga is the link