I still need to get international calls, and I don't know the number of everyone that I might want to get a call from.
I do block Withheld numbers through the BT system as I don't need to hear from anyone or any company hiding their number.
On my iPhone I'm happy to answer withhelds if I have the time to indulge in some mischief making.
There's no end of fun you can have with them, and not just by lying.
We have a phone line here which we renumber every few months. We don't give it out to anyone so if it rings, it's not for us. Normally the first few weeks are the best. We get calls looking for the person who previously had that number.... mostly it seems to be from debt collection or marketing firms. After a few calls we can usually ascertain the name and address of where they think they are calling.
If it's debt, we say the person won the lottery and moved to Florida. If it's sales we ask them to come round with a demo.
One day I got a call from a very rude guy demanding to speak to Bob. I said Bob doesn't live here any more and when pressed, rudely, for details I told the caller that Bob's wife caught him shagging a bird from work and put all of his stuff in bin bags out in the garden two weeks ago. The caller asked who I was, so I said I'm her new boyfriend, at which point he hung up. I can only imagine how that played out in the pub or at work, when the rude guy meets Bob.