Phone Number Validation
We're doomed, doomed I tell you. Given the general level of idiocy of the population (*any* population), no matter what warnings you sound or safeguards you set up, the idiots *will* fall for vishing calls, just as today they fall for phishing emails.
Trying to stop this inevitable stupidity is akin to King Canute telling the tide to turn back. (At least Canute knew he had no such power.)
Perhaps the law should be changed so chickens come home to roost: if you reveal your banking information to a third party, the resultant losses are strictly your business. Let the banks off the hook. There'll be a great weeping and wailing and gnashing of the teeth by the bleeding hearts, but good Lord! if your bank sends you a printed warning "DO NOT DO THIS" and you ignore it, surely you have to take some personal responsibility, no?
In fact, we might even encourage the 419 scammers: the more folks they take for a ride, the sooner word will get around that responding to such nonsense is Not A Good Idea.
I want to bear Paris's babies, but will settle for "Outlook not so good" as, indeed, the outlook is not good today.