I'd really like to share the VIAF website address: http://viaf.org/
This website and search engine combines authority files from national libraries from all over the world.
It is the use of authority records and the ability to disambiguate terms and names which makes library catalogues useful to searchers. It is one of the things that makes libraries stand out from information stored on the WWW in general. Libraries help users identify the specific "John Smith" they are looking for - an almost impossible task on the web.
Try the search engine out for yourself. Type in a surname, a place name and then a name of a company, institution or musical group. Notice that you will see the flags for the countries where a certain authority record is in use. If you click the heading, it will take you to the authority record in WorldCat.
I think that as we continue to think more about FRBR and FRAD we will hear increased emphasis in related discussions on using authority records and linking our bibliographic records with authorities. It makes sense to me. If this is what libraries are good at, why not make the best possible use of it?