The diameters of US quarters and pennies are very close to the ratio needed to make a truncated icosahedron, i.e., a soccer ball in the US or a football elsewhere. Copper pennies take the place of the usually black pentagons and quarters take the place of the usually white hexagons, so even the colors work out.
Besides making interesting intellectual problems, zipper unfoldings have many cool potential crafty applications as purses, bags, pillows, etc. With sufficiently rigid or reinforced fabric and the right shape, one might even make a zip-up chair, stool, table, or other furniture this way.
Old but very interesting resource from Canadian Robert Scharein, programmer of the software package KnotPlot. The knots are organized by the number of crossings, and can be clicked on to display rotatable 3D models. [via Maxwell’s Demon]
From Oxford โorigami engineersโ Weina Wu and Zhong You, published as A solution for folding rigid tall shopping bags in Proceedings of the Royal Society A. ScienceNOW has an item that at least tries to explain why this achievement is scientifically significant, rather than just really cool. Which, frankly, I donโt quite understand. But then, for our purposes, โreally coolโ is all the justification we need.
A work-in-progress from Thingiverse user searchresults. Each block has twelve 3mm supermagnets installed around its six edges, their polarities alternating so they will click together.
Use a scroll saw to make a family of complex, cube-based fractals.
…and a pretty sweet Minority Report-esque dynamic infographic (“infomotion?”), to boot. The point? The world today has more than its share of problems, but we can all be thankful it isn’t the world of 200 years ago.
The charming Swede is Hans Rosling–physician, statistician, and host of BBC 4’s The Joy of Stats. Pretty much everything about this video makes me happy, not least of all that the Brits have a TV program celebrating statistics itself. [Thanks, Dad!]
P.S. If you’re feeling cynical, check out the equally-cool-but-way-less-uplifting Animated Map of Nuclear Explosions, 1945-1998 by Isao Hashimoto.
