HUBzero allows you to create dynamic web sites that connect a community in scientific research and educational activities. HUBzero sites combine powerful Web 2.0 concepts with a middleware that provides instant access to interactive simulation tools. These tools are not just Java applets, but real research codes that can access TeraGrid, the Open Science Grid, and other national Grid computing resources for extra cycles. HUBzero was created by researchers at Purdue University in conjunction with the NSF-sponsored Network for Computational Nanotechnology. The technology was originally developed to support nanoHUB.org, a national resource for nanotechnology simulation. It has since been extended to create science gateways for other scientific domains.

The Recursive Porous Agent Simulation Toolkit (Repast) is one of several agent modeling toolkits that are available. Repast borrows many concepts from the Swarm agent-based modeling toolkit [1]. Repast is differentiated from Swarm since Repast has multiple pure implementations in several languages and built-in adaptive features such as genetic algorithms and regression. For reviews of Swarm, Repast, and other agent-modeling toolkits, see the 2002 survey by Serenko and Detlor, the 2002 survey by Gilbert and Bankes, and the 2003 toolkit review by Tobias and Hofmann [2][3][4].