I'm thinking of Regular Polyhedrons, because it would be interesting to see what edges and surfaces do when they clank in on eachother, but not just in a kinetic sense but like sheering forces and strain and all those other juicy things.

What is potential really, is it an energy embedding in space? like a blanket with hills and valleys? Because then the billiard balls work fine as a fundamental particle.

Then, we are neglecting surface areas. I think area is required to model interaction on a blanket. Like a watermelon thrown on a trampoline.

@JohnRennie but my question is, is the potential an attribute of space or is it an attribute of the particle?

Think along the lines of particle systems in blender 3d engine.