welcome to gnowsis, the Semantic Desktop environment published by the Knowledge Management Lab of the DFKI. Gnowsis is a reference implementation of parts of the Nepomuk Semantic Desktop framework.
L. Sauermann, A. Bernardi, and A. Dengel. Proceedings of the 1st Workshop on The Semantic Desktop at the ISWC 2005 Conference, volume 175 of CEUR Workshop Proceedings, page 1--19. CEUR-WS, (November 2005)