This site contains a number of live demonstrations of Intellidimension's RDF Gateway. The demos show the application of RDF Gateway to such problems as federating queries across disparate data sources, on-demand retrieval of non-RDF data sources as RDF, storing and querying large volumes of RDF data, and RDF and OWL inferencing.
All of the applications below are running on the Enterprise Edition of RDF Gateway. A free Personal Edition of RDF Gateway is available for download at http://www.intellidimension.com/downloads/rdfgateway-v2.exe. The free Personal Edition is functionally identical to the Enterprise Edition, but has a 10 connection limit and has slightly lower performance in certain tasks (due to differing cache limits between the versions). An evaluation version of the Enterprise Edition is available upon request.
Things to try: