Based on this: 
but with intelligence (Arduino), RPG LED and sensors like light (maybe acceleration?). Bigger array of light sensors so that the ball know what colors are adjacent on which side.
If in made in big numbers could be used to simulate group dynamics.
- Implement group dynamics in code
- Each ball monitors change of color in the neighbors and decides, based again on adjacent colors if it wants to be part of change, or react in the opposite direction.
- Should with 5+ balls this should result in 2 uniform color groups of balls.
I can build the tech, but I think I need help with the algos.