Random Journeys: A Mathematical Artwork by David K Butler
Used public transport tickets were attached to wooden boards according to simple rules in order to create a randomly-generated cellular automaton. Note that currently this artwork is in storage, waiting for a new more permanent home.
You can view photos of the construction of the artwork on the Facebook album here (no need to log into Facebook).
This artwork is about the fundamental struggle in mathematics between randomness and determinism and between simplicity and complexity.
Public transport tickets of the same shape were added to each panel according to four simple rules, but the choice of where to place them was left up to the people who participated. This interplay between simple rules and random behaviour has resulted in complex maze-like structures, each of which is different and yet somehow similar - each is different because of the randomness, but each contains similar structures because of the common set of rules. Moreover, while the tickets appear to be the same shape, the slight random imperfections in their shape have caused unexpected perturbations in the regular pattern produced.
When looking at the artwork, viewers are encouraged to look past the randomness to discover the rules used to construct it, and to notice the common structures in the maze that were created as the tickets were added. Thus the viewers participate in the fundamental tasks of the mathematician - to discover simplicity behind complexity, and to find the deterministic beneath the random.