This novelty pencil includes the alphabet, numbers 1-26, and other curiosities that might be useful when working through puzzles or creating and cracking codes.
This Gift Exchange item will consist of four flat pre-cut polyethylene sheets that can be assembled to produce two truncated octahedra with connectors for interlocking into the space-filling arrangement of copies of this polyhedron. Multiple…
The puzzle is strongly related to the number 14.
The trick is based on a pythagorean triple.
The size of the puzzle is about 10cmx10cmx2.5cm, and it is made by MDF.
Goal: Put all bridges on the board.
A 3D-printed copy of the 5th-level (i.e., 1024 tetrahedrons) approximation of the Sierpinski Tetrahedron.
Please enjoy the beautiful shadows under sunshine.
In particular, this object has projections with positive measure and the shadow contains an…
This is a rolling block puzzle. Roll the block from the start location to the end location. Avoid the obstacles in your path, and don't roll the block over its beveled edge. It will take some decaflops to get to the finish!
This mechanism demonstrates a surprising way to generate an ellipse by using a four-bar linkage. The shape of the ellipse can be defined by the path the intersection point of the two crossing bars follows. This fact is analogous to another neat way…
Amina Allen took a close look at the stellated dodecahedron inside an icosahedron, and found 10 squashed cubes, each with six rhombic faces that are all "fat" Richert-Penrose tiles. Has no one ever noticed before? Even Marc Pelletier never mentioned…
This wobbly spinner also called a "rattleback" features a physics defying unpredictability. Which makes it perfect for equally unsure decision making. Includes one 3¾" long rattle back and one 4½" wide decision disc.
Just as 13 breaks up nicely as the sum of 8 and 5, so too does the (volume of a) cylinder break up nicely as the sum of a cone and hemisphere, a fact we have seen demonstrated at previous Gatherings in vivid ways. But the one-diagram proof of this…