A little toy illustrating the decomposition of (a+b)^3 into a^3, 3 a^2 b, 3 a b^2, and b^3. This version has sockets for magnets to hold the entire assembly, but can easily be taken apart to count the pieces.The print file is sized in mm, so you'll have to scale by a factor of 10 if you're using MakerWare, which expects the units to be cm. The cube is held together by 3mm (diameter) x 3mm (height) cylindrical rare earth magnets. Orienting the magnets is done according to the rule: