As often happens, a lot of physics can come out of a toy. What we found interesting is the observation of the magnetic field produced by different configurations built with GEOMAG[TM]. This toy provides small magnetic bars and steel spheres to play with. Amusing 3-D structures can be built; nevertheless, this possibility is not so obvious. Indeed, in order to build a solid figure it is necessary to join at least three bars to a sphere, and therefore at least two of the poles attached to the sphere present the same polarity, but opposite poles should attract and similar poles should repel. To understand what happens, it is helpful to consider simpler configurations.