This guy designed a fake phone voicemail system and fake website with impossible CAPTCHAs to service scammers trying to redeem victim bitcoin. It's hilarious. The best part is that scammers became so frustrated, they started trying to get victims to sit on hold to scam themselves, and the scambaiters were able to extricate them from the frauds.
https://www.youtube.com/watch?v=dWzz3NeDz3E