HAL is a format you can use in your API that gives you a simple way of linking. It has two variants, one in JSON and one in XML.
First draft of HTML img srcset for responsive images
Because Salmon is an open standard, any service can implement it without formal business relationships, and Google Buzz is expected to enter the Salmon ecosystem next. If a substantial portion of the technical community implements Salmon, Facebook could be under a lot of pressure to do so as well. (As it was with OpenID, for example.) If you could still message your friends inside and outside Facebook, it would be a lot easier for innovative new alternative networks to lure you away from the one big site that 400 million people use today.
HTTP based protocol to attach meta-data to an email address
This memo describes a method for locating host metadata for Web-based protocols. Such metadata could be, e.g., crossdomain.xml, robots.txt, webfinger infos, etc.
The Open Web Foundation is an attempt to create a home for community-driven specifications.