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.
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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.
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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.