No one there is usually the result of an automatic dialler, that, lets say, calls 40 numbers,but they only have 20 operators. When 20 people, like ourselves have answered, the next 20 have no one to speak to them so the 'phone remains silent.Later it may catch up with you and you have several nuisance calls.
If I have time and feel in the mood, I like, when a male voice speaks, to say quickly, and throatily,"I've asked you not to call me at home, what we had was wonderful but it's over, don't call again".
The ones who say you have something wrong with your computer and they will talk you through it to repair it ,are good too.If they mention windows, I tell them I've got some and funnily enough am looking through one at that moment, before they can interrupt, I tell them the colour how many panes, and before long they have hung up.Or you can go along and pretend you are following their instructions to repair it, asking them all sorts of stupid questions until they give up.(hope this doesn't sound as if I am sneering) 