• Oskar's Disks
• Instant Insanity
• Archimedes' Square; Monograph
• Pathwords
• Tangramion
• Four Horses of the Epic Ellipse
• Twenty-Tans

• Garden Patch
• 3 Tiny Tans
• Trio in a Tray
• Grand Tans
• Puzzling Pentagon
• Pocket Star
• Shape by Shape

Also see on separate pages (not shown to scale):

Two nicely finished, 4" lasercut wood disks fit and move through each other's slots like a 3-D maze. It's not too difficult to solve but pleasant to do again and again. Best solution takes just 9 moves. We know of a prestidigitator who can solve it with just one hand. The linked position looks like a modern art sculpture. Cloth storage pouch is included. Oskar lives in the Netherlands and creates maze puzzles in his spare time. (Shipping discount) $35

This is the one! This classic cube puzzle has been a mind boggler since the early 1900s. It was popularized in the 1960s by Parker Brothers and was brought back by its original maker, Frank Armbruster, thirty years later. We now have his latest edition—all of them, the world's entire inventory— in well-made plastic in a slotted tray that lets you view all four sides while you're solving. The object? Arrange the four cubes in the tray so that all four sides display four different colors. This picture is not a solution. Infuriating. Each cube has all four colors, but in different arrangements, and it's extremely tricky to deduce which side should be up! If you're not familiar with this puzzle, here's your chance to experience what generations of puzzlers have struggled with. Additional challenges included, plus a poker-like game. Inquire about volume discount. (Shipping discount) $16

How cool is this? This solution can easily
transform into any tetromino (the five
shapes made of four squares), also known as Tetris pieces. If old Archie only knew!

This 14-tile dissection is the oldest documented puzzle in the world, and the decipherment of Archimedes' rediscovered manuscript is a hot topic among historical scholars and mathematicians. Also known as the Stomachion, it even made the front page of the New York Times, December 14, 2003. We are proud to offer a playable edition of this puzzle, perhaps the first publicly available in two millennia. Luminous transparent colors in a sculpted 7" tray. Long unanswered:  Just how many ways can this square be solved? On October 31, 2003, Bill Cutler's program found the full answer of 536 distinct solutions. That means rotations, reflections, and switching of identical pieces are not counted as different. (Read the full story.) How many other convex shapes can the 14 tiles make? Bernd Rennhak in Germany found all 637 solutions. He also found that the set can solve 13 of the 14 tetratan shapes. The permutations are staggering. An amazing fact is that each tile's area is a whole number, based on the square as a 12x12 matrix. That allows each of the 3 colors we added to have an equal share of the total area. Here truly is ancient genius made visible. Some of the tiles' angles have sharp points, so we recommend ages careful 10 to adult.$42

TRICOLOR STOMACHION MONOGRAPH, documenting the exhaustive study and analysis of all 1072 solutions by category, complete with illustrated Catalog of solutions and a Concordance for cross-reference. Read the amazing story of how three avid researchers pushed the frontier forward on this 2200-year-old puzzle first studied by Archimedes. Co-authored by Joe Marasco, Kate Jones and Alex Streif, you can now order your very own copy on luxurious parchment-like paper, with color illustrations.     $10.72

Click for larger view

This word search/polyomino tiling puzzle is a brilliant innovation for building vocabulary and perception skills. It won our Gamepuzzles Annual Pentomino Excellence award for 2011. A book full of letter grids and 8 polyomino shapes let you solve 80 challenges where each polyomino will cover exactly one word. Tricky as more than one word could match. Beautiful quality of see-through tiles. Endlessly entertaining and challenging for one player, ages 8 to adult.$20

Pathwords is a trademark of ThinkFun Inc.

Challenge open to the world: Find a convex or symmetrical figure not yet discovered, and we'll send you a little prize.

This 7-tile square was inspired by the dissection patterns of Stomachion (see Archimedes' Square, above), the Diamond Puzzle of T. A. Snider, and the classical Tangrams. Tangramion has amazing properties of its own. One big surprise was that the square has only 10 solutions, compared to Stomachion's 536. To date, 93 convex shapes have been identified and solved. Only 33 mirror-symmetrical and 36 rotationally symmetrical shapes have turned up so far—partly due to the fact that none of the 7 tiles themselves is symmetrical. See these and many other clever and creative designs in the Tangramion booklet (.pdf file, 303KB). In warm Lucite colors of ruby, amber, topaz, in sculpted 7x7" tray. Color mix may vary. Endlessly entertaining and challenging for one player, ages 8 to adult.$42

Tangramion is a trademark of Serhiy Grabarchuk.

What happens when an ingenious mathematician contemplates a ball pyramid piece of 5 connected spheres, its C-like shape nicknamed a horse, and imagines it flattened into connected hexagons? The resulting pentahex, in four copies, becomes a non-stop wild ride of figures to create and solve. The "epic ellipse" in the name refers to our historical Surprising Pyramid and its 2D and 3D assemblies of 4 horse-like pieces made of wooden spheres (sample shown at right). The four pentahex horses can do even more. How many symmetries can you find? How many enclosures? How many shadow figures? Lasercut black acrylic, four 3" tiles, in drawstring pouch. Illustrated leaflet provides challenges and fun for ages 6 to adult. (Shipping discount)   $12

In the beginning were Tangrams, a set of 7 tiles based on half-squares cut in half diagonally. Their basic shape was a square, and they date back to the 17th century. Here is their latest brilliant and colorful embodiment. True to their mathematical purity, the 20 tiles cover 16 squares and can form hundreds of figures. We start them as a "stretched hexagon" with color separation. Each color supplies 5 tiles, a "hand" that covers a 2x2 square and 63 other symmetrical shapes. And so can two hands, and all four hands, in ascending sizes. Explore figures with many edges and large enclosures, letters of the alphabet and picturesque designs provided in the booklet, and create your own. Play with color patterns as well. You'll never run out of challenges. For ages 6 to adult. $49