A nearest neighbors and midpoints kind of video.
Click to embiggen and more detailed description at Vimeo.
Another 2D continuous automata video.
Each pixel has a value between 0 and 1. At each iteration, each pixel's value is replaced by a value given by a function of the values of the 8 adjacent pixels, sorted so that the result is non-directional.
Click to embiggen on Vimeo.
Bigger and explanation at Vimeo: just click the darned thing.
26 particles move linearly at various speeds, bouncing off the edges. For each frame, for each pixel, find d_0 < d_1 < ... < d_25, the distance from the pixel to each particle. Then, if
2 d_1 > d_0 + d_2
color the pixel white; else, color it black.
Click through for a larger version.