I told an overseas phone sales man that i can't have any type of phone in my house as the signals will make my house blow up, had him going for 10 mins, then he got pissed off and told me to say sorry 10 times, and then i said no and was nice and rude to the willy, then he said he's gonna shoot the house... Alternatively, if they ask for someone, say, 'yeah, i'll just get him' and put the phone down. But the best ones are really weird/random excuses n stuff, much like the signals blowing your house up.