Dr Klaus Werner has been working with Intelligent Cultural Resources Information Management (ICRIM) on connecting repositories or information silos from "different cultural heritage organizations – museums, superintendencies, environmental and architectural heritage organizations" to make "information resources accessible, searchable, re-usable and interchangeable via the internet".
You can read more on these CAA07 conference slides: ICRIM: Interconnectivity of information resources across a network of federated repositories (pdf download), and the abstract from the CAA07 paper might also provide some useful context:
The HyperRecord system, used by the Capitoline Museums (Rome) and the Bibliotheca Hertziana (Max-Planck Institute, Rome) and developed as Culture2000 project, is a framework for the inter-connectivity of information resources from museums, archives and cultural institutes.
The repositories offer both the usual human interface for research (fulltext, title, etc.) and a smart REST API with a powerful behind-the-scenes direct machine-to-machine facility for querying and retrieving data.
The different information resources use digital object identifiers in the form of URNs (up to now, mostly for museum objects) for identification and direct-access. These allow easy aggregation of contents (data, records, documents) not only inside a repository but also across boundaries using the REST API for serving XML over a plain HTTP connection, in fact creating a loosely coupled network of repositories.
Thanks to Leif Isaksen for putting Dr Werner in contact with me after he saw his paper at CAA07.