When I first launched BioStor (an article finding tool built on the top of the (Biodiversity heritage Library) I wanted people to be able to edit metadata and add references, but also minimise the chances that junk would get added. As a quick and dirty deterrent I used reCAPTCHA, so anybody adding a reference or editing the metadata had to pass a CAPTHCA before their edits were accepted.
While reCAPTCHA does the trick, it can be tedious for somebody editing a lot of articles to have to pass a CAPTHCA every time they edit an article. Ed Baker of the International Commission on Zoological Nomenclature (ICZN) has a project to identify all the articles in the Bulletin of Zoological Nomenclature, and has been gently bugging me to add a login feature to BioStor. I played for a while with OpenID, but it occurred to me that Mendeley might be a more sensible strategy. Mendeley's API supports OAuth, a protocol where you can grant an application access to another application, but without giving away any passwords. It's used by Twitter and Facebook, among others. Indeed, a growing number of sites on the web are using Twitter and/or Facebook services to enable users to log in, rather than write their own code to support login, usernames, passwords, etc.
In the case of BioStor, I've added a link to sign in via Mendeley. if you click on it you get taken to a page like this:
If you're happy for BioStor to connect to Mendeley, you click on Accept and BioStor won't bug you to fill in a CAPTCHA. Once Mendeley's API matures it would be nice to add features such as the ability to add a reference in BioStor straight to your Mendeley library (this is doable now, but the Mendeley API looses some key metadata such as page numbers).
But, thinking more broadly, Mendeley has an opportunity here to provide services similar to Facebook Connect. For example, instead of simply having buttons on web pages to bookmark papers, we could have buttons indicating how many people had added a paper to their library, and whether any of those people were in your contacts. We could extend this further an create something like Facebook's Open Graph Protocol, which supports the "Like" button. Or perhaps, we could have an app that integrates with Facebook and harvests your "Likes" that are papers.
Food for thought. Meantime, I hope users like Ed will find BioStor less tedious to use now that they can log in via Mendeley.