The use of RSS 1.0 is especially prevalent in the scientific and governmental fields. There are modules available there, too. They're a little too specialized for a complete rundown, but here's a short list:
For chemists, CMLRSS enables RSS 1.0 to convey information about the structure of chemical molecules. Developed at the University of Cambridge, the authors have also made Java software available for producing visualizations of the molecules themselves.
The UK e-Government Metadata Standard (http://www.esd-toolkit.org/laws/)
The U.K. government has mandated an RDF schema for its data, and this is also available as an RSS 1.0 feed. Andrew Green has created Perl modules specifically for creating such feeds, available at http://search.cpan.org/~article/.
Creates an automatic recommendation system between weblogs, perhaps further explained by this presentation: http://matrixpn.auriga.wearlab.de/freeporter-mgain_presentation/freeporter-mgain_presentation.html.