Every single public message on Google Buzz, the content-sharing platform from the search giant, is now available to any developer. A similar, if much fatter, pipe is available from Twitter, but only for large partners paying big bucks. Accessing the "firehose" is about the same any other API, which makes it an easy way to get a lot of content quickly.
For music fans who enjoy listening to playlists on their laptops or desktops, Tomahawk is a music player with a few extra bells and whistles that may be of some interest. It's an open-source, cross-platform music player, which means it enables a user to play music stored on their own hard drives as well as from a variety of other music sources like Spotify, SoundCloud, YouTube and more. The Toma.hk API makes this functionality available to developers or users to add songs to websites.
Recently we wrote about the wonders of PubSubHubBub and what was possible when services push data, in real time, to external web apps. Twitter's Stream API makes it clear that we're headed towards an exciting and very real-time web. Now YouTube is along for the ride.