Set running to 1 to start the simulation. You can draw in squares. Use turbo mode! (shift-click the green flag)
This is the "Star Wars" cellular automata by Mirek Wójtowicz. For more info about cellular automata, read this article: http://en.wikipedia.org/wiki/Cellular_automata The grid is just large enough to see basic patterns. To start, try drawing a 2x2 red square in the center. This cellular automata's rule is: If a State-0 cell is surrounded by exactly 2 State-1 neighbors, it switches to State-1. If a State-1 cell is surrounded by 0, 1, 2, 6, 7, or 8 State-1 neighbors, it switches to State-2. All State-2 cells switch to State-3. All State-3 cells switch to State-0. State-0 is black State-1 is red State-2 is orange State-3 is yellow