DTales developed an experimental game for the “Extreme” exhibition at Milan’s National Museum of Science and Technology (http://www.museoscienza.org/extreme/): in our experience, whenever two objects collide, one or both will break, or one will end up stuck into the other, or they will bounce away from each other, or both will stop. By contrast, the collision between two particles can promote the formation of other particles which are not fragments of the starting ones, but indeed can have greater mass.
By cooperating with each other, two players can see what would happen if everyday objects could collide at the speed of light. Thrown against each other at such speed, a die, a nut or a pen can generate other objects with a much bigger mass, such as a bicycle or a mixer. With a perfect collision, the players may even create surreal objects which would turn back into everyday items in a very short time.