An editor for the specification of Graphol ontologies
Reasoner for OWL ontologies with contexts
JFact is an OWL 2 DL reasoner, based on FaCT++
Another free OWL/DL Reasoner
SPARQLINGui is a simple tool to test sparql inference queries
Yadlr toolset for many-valued inference
Tagsistant 0.6 is a semantic file system for the Linux kernel.
Epistemological Reasoner / Situational Intelligence
An abductive sciene inquiry based learning project for school kids
It's a time reasoner that can be integrated in medical applications.