INSPIRE is (contains?) a set of standard for geo-data/meta-data exchange that the EU suggests the member countries should implement. Builds on top of GML etc.
geometry2rdf is a library for generating RDF files for geometrical information (which could be available in GML or WKT). The GML and WKT is manipulated with GeoTools. The current version of the library works with Oracle geospatial databases and relies on Jena.
"The BBC has long been an advocate of Linked Data, an approach to using the Web to connect related data, or as Wikipedia puts it "a term used to describe a recommended best practice for exposing, sharing, and connecting pieces of data, information, and knowledge on the Semantic Web using URIs and RDF.""
4sr is an extension of 4store where we are implementing backward chained reasoning. Currently a subset of RDFS is supported. This set includes: rdfs:subClassOf, rdfs:subPropertyOf, rdfs:domain and rdfs:range.