This is a game that Massimo told me about, probably invented at IVIC (Instituto Venezolano de Investigaciones Científicas).

It consist of a can that you roll on one direction, but after a while it goes on the opposite one as if it had its own will. The idea is that people try to guess what kind of mechanism the can has inside to have such behavior (by following the hypothesis-test cycle of the scientific method)

Related to [reverse-engineering-games]