I just got one of these puzzles(Cast Marble - Level 4) from ThinkGeek and love the feel of it in my hands - not to mention the challenge as it still remains unsolved on my work desk. Below is a section of the Cast Puzzle website that explains the puzzles:
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Firstly, we want everyone feel the ‘cast puzzle’ by the eye and hand, to feel the movement of the geometric puzzle and to feel the metal material and the beauty of it. By this, our right brain is stimulated. In this digital society, it may be a way to entwine our hearts. The solution is not included, and the cast puzzle is just a delicate woman. One time being able to detach, it may not be easy to reset to origin. It is just like to repair a broken relationship. It is not easy. Moreover, though you could solve it now, as time passes, you may forget the method of solving.
We want you to put it by your side. Anytime as you try to solve the cast puzzle, you become pure in mind, and the refreshing impression penetrates the line of the backbone, this pleasant sensation which you do not have before.
