I use the 1572 facility as well, and it has certainly reduced the number of calls we get. The remaining nuisance calls which get through are usually pretty easy to identify, often from the unmistakeable call-centre background noises and someone with a strong South Asian accent introducing themselves as 'William' or 'Christopher' or 'Miriam'. I either put the phone down straightaway, or (if I have time to kill) amuse myself by adopting the persona of an ingenuous individual, who is concerned about the computer error/imminence of being cut off etc that they are warning me about - and eager to accept their offer of help. On occasions, I have managed to keep them talking for up to 20 minutes, as I 'get myself upstairs to the computer'; 'switch on the computer'; 'find the password which my carer changed the other day'; 'pop downstairs to answer the door' and so on - all from the comfort of my armchair or wherever - before denouncing them. If I don't have the time for that performance, I may go straight into the "What would your mother think if she knew you were trying to cheat innocent people?" mode. Great fun to be had at these criminals' expense. It probably does not get my number put on their own blacklist, but it certainly amuses me..