Sebastian Trüg has published a first screencast of the NEPOMUK-KDE project, which brings the power of RDF‘s resource annotation to the KDE desktop environment for Linux (wikipedia).
The first feature is annotation of files with text, rating, and tags. The same is possible for e-mails, websites, and everything else you can think of. Underlying is not a simple model of tags-as-strings, but RDF. Thus, you can easily rename tags and do other nice things, such as semantic desktop search.
The screencast as such is a bit too long and without sound, not very brushed yet. But I bet that once more features are implemented, there will be nicer presentations.
Using RDF on the desktop opens now possibilities to improve publishing data on the web, tags and annotations added to files can easily be added to websites, and vice versa, data downloaded from the web to the desktop can be linked to additional information from the web.
A little background: The NEPOMUK-KDE project is supported by the European Union and helps building a platform for other semantic applications to build upon. This is part of the Lisbon Goal of the EU to become “the most competitive and dynamic knowledge-driven economy by 2010“. The know-how to do these things is currently developed in the union, companies and solution providers may then build upon this.