On our (virtual) bookshelves:
Download the list as .csv file: OSP-library_030810
The OSP-library is a modest pile of books that we think is relevant to our practice. Some we have read and others we should. We'll keep adding titles; suggestions welcome!
After testing several ways to catalogue the collection, we settled with LibraryThing for the time being. It's not ideal ... though it is a good project (they allow users to export collections as .csv file (book data, no tags), use multiple sources for bibliographic data and have a sensible privacy policy) the software nor data is under a free license.
We tried Alexandria and than exported our booklist as a static html page but the amount of times the software crashed drove us insane. Also it is a bit disappointing that Alexandria almost completely relies on data from amazon.com. A rewrite is on it's way so we are looking forward to that. We most of all want to use http://www.openlibrary.org, a project initiated by http://www.archive.org. We like their concept "a wiki page for each book" and the site contains a fair amount of information already. For posts on individual books, we started to use a plugin that can pull data from http://www.openlibrary.org. But we'll need a bit of patience before jumping ship: the team is currently working on adding the indispensable feature that allows us to make lists. And the ability to import data from file would be nice too!