SmoothLife (2011)
I’m fond of artificial life experiments–like Conway’s Game of Life, to pick the most common example of cellular automata–so this extension of the idea to use floating points values has been in my bookmarks for a while.
Stephan Rafler, who came up with this family of rulesets, explained how it worked with these slides, but the basic idea is that instead of looking at neighboring cells, it looks at the a circular region instead. Unlike some other attempts to generalize Life to a continuous space, the SmoothLife rulesets include many of the interesting features of Life, such as gliders.
The result is a very organic-looking simulation.
The source code is on SourceForge, though it may be easier to run the version that’s implemented as a ruleset for Ready.