My latest riddle:
A woman had two identical letters. They both were made out of the same paper and were placed in identical envelopes with no other contents. She put exactly 41 cents postage on each one. She put both letters in the same mailbox. Both letters went to the same address and were sent First Class. Yet one of the letters went to its destination, while the other was returned for more postage. Why?
NOTE: The correct answer has been guessed. Please see the comments section for the answer.
Lateral Thinking Puzzlers by Paul Sloane has lots of classic riddles, clues and answers. Click here to order it.