[math-fun] World's Hardest Burr Puzzle, now in stores everywhere

At the Gathering for Gardner last year, I suggested to Bill Ritchie that he manufacture Frans de Vreugd's Extreme Torture puzzle. It was an extreme mathematical anomaly. I wrote a column about it: http://www.maa.org/editorial/mathgames/mathgames_08_02_04.html My thinking was it's fun to take a puzzle apart, and this is a puzzle where taht fun part will last a *long* time. Well .. Thinkfun has released the world's hardest puzzle, under the name Gordian's Knot. And it looks so cute: http://www.puzzlemethis.com/cgi-bin/puzzle/THK06820.html Ed Pegg Jr