Learning swear words in Hindi and just letting them have it. Better than therapy. Call them untouchable, it’s scathing.

By answering then muting the mic.

Costs them a couple cents in call costs and a little time as the wait for me to say anything. Eventually the calls stop because after enough invalid answers the number is marked as bad.

I’ve seen videos of people putting two spam callers on two phones next to each other so they talk together