Feedreader is a lightweight open-source aggregator that supports all major RSS/ATOM formats.

This is an open-source aggregator that supports all major RSS formats. It has a small footprint and support for multiple languages. FeedReader supports all major syndication formats including RSS 0.9, 0.91, 0.92, 1.00, 2.0 plus Dublin core and Slashback extensions. It provides alerts about incoming feeds on the taskbar and caches headlines for offline viewing. It also supports proxies and allows one-click subscription of Radio Userland and AmphetaDesk feeds.

Features:
1. Supports all major syndication formats: RSS 0.9, 0.91, 0.92, 1.00, 2.0 plus Dublin core and Slashback extensions
2. Pre-configured with hundred of quality feeds from leading syndicators such as NewsIsFree and Moreover
3. Alerts about incoming feeds on taskbar
4. Caches headlines for offline viewing
5. Supports proxies
6. Allows one-click subscription of Radio Userland and AmphetaDesk feeds
7. Search support
8. Multilanguage support
9. OPML import and export.

The license of this software is Freeware, you can free download and free use this rss reader software.