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useful stuff Excellent cheap puzzle book: The Moscow Puzzles: 359 Mathematical Recreations Mark Frauenfelder

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puzzles Can we wrap a 1x1x1 cube with the blue 3×3 piece of paper, cutting along some edges without disconnecting it? Mark Frauenfelder

puzzles Can you solve the virus riddle? Mark Frauenfelder

puzzles A hat puzzle Mark Frauenfelder

brain teasers Brain teaser: draw a cross inside the grid Mark Frauenfelder

brain teasers Puzzle: The Candy Thief Mark Frauenfelder

math The best place to sit in a "suicide circle" if you really don't want to die Mark Frauenfelder

puzzles The best book of physics brain teasers Mark Frauenfelder

puzzles The Missing Dollar puzzle from Martin Gardner's Aha! Gotcha book series Mark Frauenfelder

makers Build this brain-teasing golf ball in a block of wood Mark Frauenfelder

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video games Professor Layton series to receive first mainline installment in 10 years Grant St. Clair

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