Here is a wiki for semantic web developmental tools...
This page contains the information on RDF and OWL tools that used to be listed on the home pages of the RDF and OWL Working Groups at W3C. Keeping such lists up-to-date is obviously a problem when the number of Semantic Web tools increases every day. By moving this list to the Wiki, we hope that the community at large will help maintain these pages.
This Wiki page is only for programming and development tools. For a more comprehensive information on RDF in general, which also includes articles, descriptions, etc., the reader should refer to Dave Beckett's Resource Description Framework (RDF) Resource Guide.
The page maintained by Chris Bizer and Daniel Westphal at the at the Freie Universitt Berlin also gives a more thorough comparison of some of the development tools (including licensing, reasoning support, etc).
A similar source of information is Michael K. Bergman's list which also lists tools are related to Semantic Web though not necessarily using the core technology (eg, natural language ontology tools).
These are all some great resources for anyone interested in the Semantic Web.