This brain teaser comes courtesy of www.braingle.com:
Three-year-old Sam has just learned to count to 30! He especially likes to read the clock when the numbers are in order. For example, he likes 3:45, which he sees not as three forty-five, but as three, four, five. Can you find all the times when the numbers on a clock are in sequential order?
Will post the answer in a day or two in the ‘comment’ section.