Just announce loudly and to a lot of people is sending you retarded text messages, and it's quite funny how they're wasting their own money doing this. Make sure to show it too a lot of people too, so they can all have a laugh at the senders' expense.

Make comments about how such anonymous threats are probably made by a girl you dumped, since no real MAN would ever be such a wuss. Imply homosexuality if a guy does do this.