Thanks everyone. Some of you responses are brillant. It is moments like this that I wish I had the quickness of mind to come up with something really devastatingly Oscar Wilde funny. But it always happens after the event.
The other one is a particular nickname that people give me (a variation on my actual name). There are some people I can accept it from but others I can't. I think it is those who assume a sense of familiarity with you that you would much rather them not have, who are the ones I hate doing it and I usually end up telling them so.