Richard Wallis at Talis has written an extension for the FireFox browser which gets you to information in any of 50M (and growing) library holding records. It works in conjunction with Tim Spalding's LibraryThing service. I'd describe this as a social collection cataloguing system. You stick in some book details and the service searches a bunch of libraries and other sources and offers to 'fill in the blanks' for you.

You can be anonymous and just search for stuff or you can fully participate, adding up to 200 titles, tagging them, rating them etc. If you have more than 200, you will have to pay a modest annual fee.

Wallis' extension is called LibraryThingThing, a mashup which takes the ISBNs of the found records and checks with the XISBN web service to see if there are any more numbers. Then it looks at the Talis holdings database to list the libraries where the books can be found.

You choose a library, and the mashup then takes you, via the Talis directory, to either the book record in the library, to the library, to the collection or to the Silkworm collection entry in the Talis directory platform. In other words, LibraryThingThing gets you as close as possible to the record you want.

It costs nothing to add records to the directory of collections, which is run in a wiki-like way, so there are minimal financial and technical barriers to adding collection, library and service (OPAC) connection methods. This is intended to become a global, open resource, although it does have a UK bias at present.

And, just like the directory, the source code of LibraryThingThing is available for anyone to use and extend.