Seen in the humor thread (paraphrasing as I remember it):
Me: (blanking on person's name, so using this trick) You have an unusual name. How do you spell it?
Him: D-A-N
Me: (long pause) Oh, so only one N.
Me: (blanking on person's name, so using this trick) You have an unusual name. How do you spell it?
Him: D-A-N
Me: (long pause) Oh, so only one N.