While del.icio.us is delicious, fac.etio.us isn’t facetious. It’s a thought experiment embodied in software from Siderean, a company that creates faceted classification systems for big-ass enterprises. (Note the “facet” in “fac.etio.us”? Damn clever!)

Faceted classification assigns a set of parameters (facets) to the objects it’s classifying and then lets users sort them using the facets in any order. For example, appointments in your calendar might have facets for time, date, person, location, subject, and importance. You could then ask to sort first by person, then by location, and then by date, and a minute later walk through them by importance, then date, then subject, etc. In short, faceted classification systems let you construct trees with the roots and branches in whatever order suits you at that moment. And faceted systems never lead you down branches that have no fruit.

So, Siderean is playing around with doing a faceted classification of about five days’ worth of bookmarks at del.icio.us.

In an email, this is what Bradley Allen, the founder and CTO, says:

Currently this is being updated hourly from three feeds: delicious, delicious/popular, and my own inbox feed. The RSS feeds are being transformed into slightly richer RDF using the Dublin Core and SKOS vocabularies, then loaded into Seamark and made navigable using dc:subject (tag), dc:creator, dc:publisher (site), dc:moderator (feed) and dc:date as the facets.

At the fac.etio.us home page you’ll see all five facets exposed: tag, creator of the tag, site tagged, the feed it was found in (del.icio.us, del.icio.us/popular, and Brad’s feed), and the date the tag was created. You can click on any, but let’s say we click on one of the entries in the list of Tags: Music. We are taken to a page that lists all the bookmarks tagged “music,” but are also shown a list of all the other tags given to all pages tagged with “music,” all the people who have tagged a page “music,” all the feeds that contain bookmarks tagged “music,” and every day in which someone has used the “music” tag. Each of these is itself clickable.

Oh, to hell with describing it. Give it a try!

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