San Francisco team wins paper shredder puzzle prize
sfgate.com
sfgate.com
Then he happened on an article about a little-known government project: The Secret Service has been working with manufacturers of color laser printers to place tiny, imperceptible yellow dots on printed pages so that the government can track the machine that produced them. Good put the puzzle under a blue-light filter and saw the dots.
That's a great hack! Kudos to the team.
I need to fire up those 'orthogonal thinking' neurons!