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The Hardest Logic Puzzle Ever
The Hardest Logic Puzzle Ever is a logic puzzle invented by American philosopher and logician George Boolos and published in The Harvard Review of Philosophy in 1996.
A two-dimensional representation of the Klein bottle immersed in three-dimensional space
Klein bottle
Make: Online | Japanese Gravity Marimba Plays Bach In An Ancient Forest
<img src="http://makezineblog.files.wordpress.com/2011/04/japanese-gravity-marimba.jpg?
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