Flame
I got thinking about how fires work today. Why do flames curl into whorls and some tongues lick up so high? I built this model to see how hard it was to reproduce the phenomenon. This is the result. I don't think it captures much of the underlying mechanism but it looks pretty hot 
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Flame
A [NetLogo] model by Rik Blok.
http://www.zoology.ubc.ca/~rikblok/wiki/doku.php?id=science:popmod:flame:start
This is a simple particle-based simulation of flames. Individual "particles" of flame are produced at the bottom of the world and burn as they float up. It's not meant to capture real fire dynamics but just simulate the look.
References
[[NetLogo]] Wilensky, U. NetLogo. http://ccl.northwestern.edu/netlogo/. Center for Connected Learning and Computer-Based Modeling, Northwestern University. Evanston, IL. 1999.
Rik Blok