Playful thinking
Happy Cubes are a set of mechanical puzzles created in 1986 by the Belgian toy inventor Dirk Laureyssens. Until 2003, the company “Happy n.v.” had the exclusive license to manufacture and sell these puzzles[1]. However, several other vendors have produced these earlier in the 80s or 90s or before 2003. Happy Cubes are also known by a number of other names, among them: “Cube It!” cubes, “Wirrel Warrel” (in Holland), “I.Q.ubes” and “Cococrash” (in Spain).
The Happy Cubes were made of 8mm-thick ethylene-vinyl acetate foam mats (also known as EVA). The tiles were based upon a 5×5 matrix where the outer squares may be present or absent. The central 3×3 kernel was fixed. Initially the puzzle is assembled into a 2-dimensional, flat 2×3 piece rectangle fitted into a frame. The basic challenge is to construct a perfect, 6-sided cube out of these 6 pieces. Usually, there is only one way to fit the pieces into a complete cube and it can be reached with various levels of difficulty by trial and error. – Wikipedia
Download a program to play here. Read about the game in Spanish here.
I have never played with this puzzle. Have you?