If there is one thing guaranteed to raise my blood pressure it is surely those annoying telephone calls claiming to be from (BT/Microsoft/[insert your 'favourite' here]) and warning you that your computer is at risk or that your internet is about to be switched off unless you click 1 to speak to an adviser.
When it comes to calling out scammers for blatant lies and shaming them for criminal actions, no one did it better than a friend of mine BBC Click reporter Kate Russell. In 2011, Kate was told by her parents about a call from a "nice gentleman from an Indian call centre" claiming that their computer was infected with a virus. Russell took the next call herself and recorded the telephone conversation which you can listen to here soundcloud.com/kate-russell/phone-scammer-busted (Reproduced by courtesy of CreativeCommons.org open licence).
The call lasts about 16 minutes and Kate manages to keep a straight face/voice throughout whilst listening to his spiel. Unless you wish, I wouldn't bother listening to all of his rantings but click on the spikes in the sound trace bars (indicating where Kate is speaking). The outcome is hilarious and should be required listening for anyone tempted to respond to one of these bogus calls.
Remember that reputable companies will not cold call you like this. BT does NOT arbitrarily switch off people's internet connections (unless they have given prior warning for something like non-payment of bills). Remember that scam callers have not singled you out for any particular reason; they are simply ringing their way down a long list of numbers. Remember NEVER to agree to type in a series of numbers or a code to allow them access. If your phone is provided by BT set up their free Call Protect service which enables you to block the last call to your phone. Other providers have similar schemes.