Since the recent release of a new tool from Yahoo! - Yahoo! Pipes - developers have been working with it and creating their own "pipes" of functionality, already exploring the boundaries of the application. Clay Loveless is one PHP developer that has already created his own pipe to monitor feeds from several PHP extensions.
The first pipe I've created and published is the PHP Extension Monitor. It's an aggregated feed that pulls in release information on several cool extensions that aren't announced in the PECL feed, such as Suhosin, XCache and DBXML.