The above file is a cellular automata simulation written for a computational physics class. It was inspired by Conways Game of Life.
Based upon a set of initial conditions, namely the placement of cells and the rules guiding how they might interact, a chain reaction unfolds that resembles the emergent complexity that John Conway found so interesting in conceiving this little game.
As the extension suggests, this file is meant to be run in Mathematica. Consequently, the code is formatted for Mathematica's GUI, and therefore nigh unreadable in its current form. To remedy this issue, download Wolfram CDF Player and you'll be able to view the text without the nagging 'Cell' and 'Rowbox' markers strung along the margin. A warning: The CDF Player isn't the smallest application, as such it will take a bit to download and install.