Vienna is an open source Mac OSX RSS reader with support for RSS/Atom feeds, article storage and management via a SQLite database, written in Objective-C and Cocoa.
Feeds can be accessed directly, or through a syncing service supporting the Open Reader API, like BazQux.com, FeedHQ.org, InoReader.com or TheOldReader.com.
Development now happens on GitHub: https://github.com/ViennaRSS/vienna-rss
- smart folders
- social sharing
I use Vienna RSS since two years and I'm still very happy to use it daily. My feeds are synchronised with the FeedHQ service and Vienna deal perfectly with it.
The most interesting site that I know!!!