Photoshop filters bear a striking resemblance to the cellular automaton, Conway’s Game of Life. Just as Photoshop compares neighboring pixels to the current pixel and then adjusts its value, Conway’s Life compares neighboring cells to the current cell to determine whether it lives or dies.
Realizing this, I thought I would make a simple Photoshop action which implements Conway’s algorithm. It uses the Custom filter to blend neighboring pixels. A Gradient Map pushes the pixels back to black and white.