This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. NAMD (Nanoscale Molecular Dynamics, http://www.ks.uiuc.edu/Research/namd/) is a parallel molecular dynamics code designed for high performance simulation of large biomolecular systems [1, 2]. NAMD employs the prioritized message-driven execution capabilities of the Charm++/Converse parallel runtime system (http://charm.cs.uiuc.edu/), allowing excellent parallel scaling on both massively parallel supercomputers and commodity workstation clusters. NAMD is distributed free of charge to over 30,000 registered users as both source code and convenient precompiled binaries. 6000 users have downloaded multiple releases. NAMD 2.7b1 was released in March 2009 and in six weeks since its release has been downloaded by over 1,300 users, 200 of whom are NIH-funded.