Note that a few links appear to be outdated. Free download, instructions on use, and postscript versions of a paper and a talk on the topic are all available online. The official Gnu Public License Web server, with essentially complete lists of links to download sites and online documentation for the complete array of Gnu software. The list, including over 5000 entries, is organized alphabetically. Also provided is a database of material properties and a list of important constants.
All information is available for free download.
At the time of this writing, the amount of information is somewhat limited, and the total number of categories is still small, but given adequate support may become very useful. All codes are available for free download. Documentation is provided in the source. Not fancy, but there are some excellent links here. Postscript and PDF file formats are provided.