ThingISBN

Librarything has just released thingISBN, a service which overcomes the inadequacies of the ISBN. ISBNs identify editions well, but are useless if you want to see what exists at a higher level; see the Functional Requirements for Bibliographic Records (FRBR to its friends) which gives a hierarchy of, in descending order, work-expression-manifestation-item.
I'm not quite sure yet how I can use this: I suspect its mostly for the more technically-minded librarything users.