PUZZLE COFFEE TABLE
This piece is based on a puzzle in geometric dissection. The problem is how to cut an equilateral triangle into pieces that can then be assembled to form a square.
It was possible to turn this puzzle into a three dimensional object by proving that the segments could be reassembled simply by rotating them.
The segments are fixed in either the square or triangular arrangement by a thumb-catch. Simply slip the catch and pivot the segments 180º and the triangle becomes a square! or the square turns back into a triangle.
It is more a toy than a piece of furniture, but it has led to these ideas being applied to more practical problems.