Browse Items (22 total)

ExchangeArchive-Pencil-G14-037-1.jpg
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.

ExchangeArchive-Tetradecahedra-G14-034-1.jpg
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…

ExchangeArchive-14Bridge-G14-021-1.jpg
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.

ExchangeArchive-SierpinskiTetra-G14-012-1.jpg
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…

ExchangeArchive-BlockRoll-G14-003-1.jpg
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!

ExchangeArchive-Klein-G14-017-1.jpg
3D printed klein bottle

ExchangeArchive-Ellipse-G14-063-1.jpg
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…

ExchangeArchive-SliceOfSpace-G14-033-1.jpg
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…

ExchangeArchive-Superposition-G14-004-1.jpg
Physical gift a small E link puzzle and a puzzle postcard.
Paper 'Multiplication by Superposition' - PuzzleAtomic.com

ExchangeArchive-ForestCards-G14-010-1.jpg
Text by: David G. Haskell,
Illustrations by: Ellen Litwiller

ExchangeArchive-Celt-G14-066-1.jpg
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.

ExchangeArchive-PatternStacker-G13-064-1.jpg
An abstract spatial thinking pattern puzzle

ExchangeArchive-Cavalieri-G13-048-1.jpg
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…

ExchangeArchive-Lights&Spheres-G13-050-1.jpg
A 7cm green plastic sphere with a surface of conical projections, otherwise known as a Cando Massage Ball.

Titanium LED keychain flashlights: I will ship 200 with white LED, 100 with red, blue and green LEDs. Each attendee will receive one light…

ExchangeArchive-PonyRubiks-G13-069-1.jpg
My Little Pony, 2x2, Rubiks Cube

ExchangeArchive-Pentagons-G13-031-1.jpg
This item for the Gift Exchange is a 3D printed baker's dozen of irregular pentagons that tessellate the plane.

G4G-ExchangeArchive-G4G13-GoldenMagic-(1).jpg
Unofficial logo designed for G4G13

ExchangeArchive-4x13-G13-020-1.jpg
There are 52 cards in a standard deck of playing cards: four suits of 13 cards each. To design a deck of cards, one needs to establish the four suits, each with its own symbol and/or concept, and find a logic for generating the 13 cards in each suit,…

ExchangeArchive-Surprise-G13-079-1.jpg
A small booklet of 20 math puzzles that involve the element of surprise. Some appear to lack sufficient information to solve; others run counter to one's intuition as to what the answer should be.

ExchangeArchive-Spiram-G13-015-1.jpg
Physical physics toy gift for the exchange: A craft kit with all parts needed to crate a tiny kinetic sculpture based on the physics of equilibrium, magnetic force, and angular momentum.

ExchangeArchive-CardDice-G13-082-1.jpg
This pair of unique dice consists of a 13-sided die with both numbers and face-card labels for J, Q, K, and A, along with a 4-sided die with the standard playing card suits.

ExchangeArchive-Lucky-G13-024-1.jpg
A dissection puzzle involving the characters G413. Exact puzzle to be determined...
Output Formats

atom, dcmes-xml, json, omeka-xml, rss2