The Del.icio.us Java library by David Czarnecki was created years ago to interact with del.icio.us API. What this service does is to bookmark favorite websites that can later be accessed online from anywhere. The RESTful API works via HTTP and returns XML responses. For any updates, contact the author email@example.com
During undergrad, I worked on a few side projects, with most of them using some sort of social-networking API. It was great learning some new skills and at the same time it was rewarding to tap into the vast networks of established sites such as Facebook and Twitter. Cue to postgrad and I had to complete a research component as part of my course requirements. With a nudge from my supervisor I asked the question: "Is it viable to have a generic social networking API? Will it be useful?"
Microsoft has released a suite of tools to integrate its popular Messenger client into your website. Called Messenger Connect, the new API embeds a Windows Live Messenger chat window on your site, which enables visitors to share links, collaborate, or just stay connected to friends.