Cubes.io

Cellular automata are systems which contains grid of cells and a rule which governs the cell's evolution.
The cells have finite number of states, which is on and off. So each time the system evolves, the rule applies '"on and off" states to determine the new configuration of cells.

With cubes.io you can explore the idea about 3d cellular automate called "totalistic". The future of the evolution depends upon how your initial grid has been setup.
There are various tools you can explore to experiment different results. You can choose different shape and sizes, rotate them, choose different numbers of cells and many more.
You can choose different rules by which the cells behave and evolve in each generations. After you press play and start evolving them they create wonderful and interesting shapes and are entertaining to watch.