http://blogs.publishersweekly.com/blogs/PWxyz/2013/06/13/the-best-apis-are-simple-web-standards/

An interesting idea, though what kind of links work like this?

"we’re working on building software to support annotation of web documents. One of the obvious challenges is to make sure that comments on one version of an item appear on a related version; the problem is akin to a reader wanting their comments on one edition of Huck Finn appearing on a second printing of that title, even if it has a different ISBN."