An auto-adaptive genetic system designed primarily for use as a platform in Digital or Artificial Life research. Download source, binaries and documentation. Unix/Windows. http://dllab.caltech.edu/avida/
A web-oriented artificial-life site: Alife, genetic-algorithm and cellular-automata experiments written in cross-platform web languages (Java, tcl/tk), with free source code. http://www.aridolan.com
A sourceforge project for an environment for creating and running agent-based models. Tcl/Tk scriptable, cross-platform (Windows and Linux/Unix). http://ps-i.sourceforge.net/