AmphetaDesk
Desktop-based feed reading software.
http://www.disobey.com/amphetadesk/

Anothr
Anothr describes itself as "a Skype-based robot which can provides just-in-time alerts for your favorite feeds".
http://www.anothr.com/

Awasu
Trawls your favourite websites and alerts you when there is any new content on them.
http://www.awasu.com/

Bloglines
An integrated service for searching, subscribing, publishing and sharing news feeds, blogs and other web content.
http://www.bloglines.com/

BlogMatrix Jager
Open source blog aggregator.
http://jaeger.blogmatrix.com/

BottomFeeder
RSS and Atom feed viewer.
http://www.cincomsmalltalk.com/BottomFeeder/

Feed Validator
Checks RSS and Atom feeds, to make sure they are working properly.
http://feedvalidator.org/

Feedburner
Create an RSS feed your weblog.
http://www.feedburner.com/

FeedDemon
Desktop RSS feed reader from Newsgator.
http://www.newsgator.com/

Feedmailer
Receive RSS feeds via email.
http://www.feedmailer.net/

Feedreader
Lets you follow updates on news and blogs sites with ease.
http://www.feedreader.com/

FeedShow
Feature-packed online feed reader.
http://www.feedshow.com/

Google Reader
Keep abreast of changes on your favourite websites with this tool from Google.
http://www.google.com/reader/

Liferea
A Linux feed reader that supports a number of different feed formats including RSS/RDF, CDF, Atom, OCS, and OPML.
http://liferea.sourceforge.net/

News Alloy
Read and share news and information with free Web-based feed reader.
http://www.newsalloy.com/

NewsGator
Popular web-based RSS aggregator.
http://www.newsgator.com/

NewzCrawler
Monitor time-sensitive web content with the aid of this RSS/atom reader, news aggregator, browser and blog client.
http://www.newzcrawler.com/

PC World
An excellent article that tells you how feed readers work and offers a comparison of some of the most popular ones.
http://www.pcworld.com/resource/printable/article/0,aid,116018,00.asp

Pluck
Pluck retrieves, organizes and automatically delivers your favorite web stuff in a single-view.
http://www.pluck.com/

Rojo
Use this free feed reader to get updates on your favourite websites and blogs.
http://www.rojo.com/

RSS Reader
A free RSS reader that is able to display any RSS and Atom (XML) news feeds.
http://www.rssreader.com/

Sauce Reader
Sauce reader is a user-friendly full-featured feed reader.
http://www.synop.com/Products/SauceReader/

Sharp Reader
Works away in the background to bring you the latest updates from your favourite websites.
http://www.sharpreader.net/

Stepno.com
Details the pros and cons of a handful of feed readers.
http://www.stepno.com/pcworld/5rssreviews042804.html

Yahoo! Pipes
An interactive feed aggregation and manipulation tool from Yahoo!
http://pipes.yahoo.com/pipes/