Bob's Your Uncle

Got home early(ish) and in a good mood for once, so time & temperament for a card trick. I don't know many. In fact I only know one. But it's quite a good one. If only I could remember exactly how it goes. On the third attempt I nailed it, and the girls loved it. "How did you do that!?" Bit of maths, bit of luck. The luck bit - if it goes right - is the winning element. I had an Uncle Bob who could do card and magic tricks. Don't remember who he was married to, where he lived, what his job was... other than the fact that he could produce a sixpence out of your ear.