[Kagen Sound] is a woodworker and artist who gives a great behind-the-scenes look at his amazingly high-quality puzzle boxes (video). Not only do his varied puzzle box designs show his math ...

“There is no more difficult puzzle, just more complex.” Scroll on for hard puzzles that demand everything you’ve got. While at it, check out this expert jigsaw puzzle strategy to solve it in ...

Test your problem-solving skills with Box Two, a new escape game from Neil Patrick Harris.