http://grey.colorado.edu/emergent/index.php/Main_Page
<a href="http://grey.colorado.edu/emergent/index.php/Main_Page">Emergent </a>(a major rewrite of <a href="http://www.cnbc.cmu.edu/Resources/PDP++/PDP++.html">PDP++</a>) is a comprehensive simulation environment for creating complex, sophisticated models of the brain and cognitive processes using neural network models. ... It includes a full GUI environment for constructing networks and the input/output patterns for the networks to process, and many different analysis tools for understanding what the networks are doing. It has a new tabbed-browser style interface with full 3D graphics (via OpenGL and Open Inventor/Coin3D), and powerful new GUI programming tools and data processing and analysis capabilities. The PDP++ software is a neural-network simulation system written in C++. It represents the next generation of the PDP software originally released with the McClelland and Rumelhart "Explorations in Parallel Distributed Processing Handbook", MIT Press, 1987.