RSS News aggregators for your desktop

You can read RSS feeds through RSS Aggregation desktop programs, or RSS Aggregation webpages. Listed below are some popular RSS Aggregation programs for various platforms.
What is RSS?
BTL recommends Awasu for Windows, NetNewsWire for Mac OS X, Liferea for Linux, and the Sage Firefox plugin for all platforms.

For Windows:

Awasu

http://www.awasu.com

Feedreader

http://www.feedreader.com/

infoSnorkel

http://www.blueelephantsoftware.com/

NewzCrawler

http://www.newzcrawler.com/

For .Net Framework (possibly to work on Mono)

SharpReader

http://www.sharpreader.net/

GtkSharpRSS (requires Gtk#)

http://gtksharprss.sourceforge.net/

For Mac:

NetNewsWire

http://ranchero.com/netnewswire/

NewsFan

http://www.makienterprise.com/newsfan/

NewsFire

http://www.newsfirerss.com/

NewsMac

http://www.thinkmac.co.uk/newsmac/

Plucky

http://www.geoffreygrosenbach.com/plucky.html

PulpFiction

http://freshsqueeze.com/products/pulpfiction/

SlashDoc

http://homepage.mac.com/stas/slashdock.html

RocketInfo

http://demo.rocketinfo.com/desktop/

For Linux:

Liferea

http://liferea.sourceforge.net

Straw

http://www.nongnu.org/straw/

For all platforms:

As an application/plugin

Amphetadesk

http://www.disobey.com/amphetadesk/

Sage (a plugin to FireFox)

http://sage.mozdev.org/

Mozilla’s Thunderbird email client

http://www.mozilla.org/thunderbird/

As an accessible webpage aggregation

Bloglines

http://www.bloglines.com/

Fastbuzz

http://www.fastbuzz.com

NewsIsFree

http://www.newsisfree.com/

Livejournal (Livejournal allows subscriptions to RSS and Atom feeds via their friends list mechanism.)

http://www.livejurnal.com