Vienna is a freeware, open source RSS/Atom newsreader for the Mac OS X operating system. It provides features comparable to commercial newsreaders, but both it and the source code are freely available for download.
A summary of some of its features:
- Subscribe to Atom/RSS news feeds and podcasts.
 - Simple and intuitive user interface.
 - Built-in tabbed browser.
 - Smart folders for organising related feed articles.
 - Custom article display styles.
 - Full AppleScript support.
 








