I only do it intentionally now, tinks. Many moons ago some chap came to the office I worked in to make an appointment. I recognised him but could not recall his name, so I asked him his name. He replied - you know my name. I said - I do, but I can't recall it, so what is your name please? Twit replied, with a leer, - you DO know my name. I said - I will do when you tell me what it is. Then about 3 more silly statements came from him. I asked once more for his name saying I couldn't book him an appointment without his name. As he opened his mouth to reply, I had the light bulb moment and remembered his name (it was Boyle). He said to me - 'pain in the arse'. I replied, dead cool - 'indeed you are Sir, but what is your name?
One of my better work anecdotes and absolutely true : o)