- eMule
eMule is a new filesharing client which is based on the eDonkey2000 network, but offers more features than the standard eDonkey client, because it's opensource but under the restrictions of the GPL License. With eMule you can download video ( divx ), music ( mp3 ), etc.
http://www.emule-project.net/

 
 - Wippit
The world's first legitimate P2P music subscription service, Wippit has over 60,000 recordings from over 160 record labels, enough to keep even the most dedicated music fan busy for a year! If you're a music fan Wippit is the only service that can give you an artists music on MP3, on your phone with a Wippit Ring Tones - you can even search from your phone too with Wireless Wippit.
http://www.wippit.com/

 
 - Fight SARS, The D2OL Project
Finding a cure for serious diseases such as SARS and anthrax involves many years of research. Help speed up the search for a cure for SARS by participating in the D2OL project from the Rothberg Institute for Childhood Diseases. To take part, all you need to do is download a small program that takes advantage of your computerís unused calculating power to evaluate the potential of candidate drugs.
http://www.d2ol.com

 
 - FtpWolf
FtpWolf is an Internet file search utility. It can search, filter and compile the results from 26 FTP engines on the Internet and deliver the Information to your browser for downloads. FtpWolf can search most of the world's FTP search engines concurrently, via a single interface, and in a matter of seconds.
http://www.trellian.com/fwolf/

 
 - KaZaA
KaZaA is a media community, where the community members can share their media files with each other. KaZaA Media Desktop is a full featured peer-to-peer file sharing application.
http://www.kazaa.com/us/index.htm

 
 - eDonkey
eDonkey is a file sharing agent. It allows to transfer any type of file, MP3, images, etc. The main advantage of this agent is its ability to download films in DivX and MPEG format. eDonkey2000 doesn't rely on one central server, the servers can be located anywhere at any IP address.
http://www.edonkey2000.com

 
 - Audiogalaxy
The Audiogalaxy Satellite is a small and simple program that allows you to share your music with friends and other users on Audiogalaxy.
http://www.audiogalaxy.com/satellite/

 
 - WinMX
WinMX is a file-sharing program like no other. It allows you to simultaneously connect to many established networks based on the Opennap and Napster protocols. This means more users and more search results. WinMX also supports any file type, allowing you access to a diverse assortment of shared video and picture files as well as the usual MP3 audio files.
http://www.winmx.com/

 
 - Morpheus
Search all the major file-sharing networks and connect with users of Kazaa, iMesh, eDonkey, Overnet, Grokster, Gnutella, LimeWire, G2, and others with Morpheus, the only American file-sharing software ruled legal by a U.S. federal court.
http://www.morpheus.com/

 
 - Diet K
Diet K removes spyware, blocks pop-ups, and gives users dozens of new features to configure the file-sharing client Kazaa Media Desktop. Speed up your downloads with a built-in advanced download accelerator and notification system.
http://www.dietk.com/