Top 25 Projects on www.SourceForge.net:

1. Azureus
https://sourceforge.net/projects/azureus
Azureus is a powerful, full-featured, cross-platform bittorrent client.

2. phpMyAdmin
https://sourceforge.net/projects/phpmyadmin
phpMyAdmin is a tool written in PHP intended to handle the administration of MySQL over the Web. Currently it can create and drop databases, create/drop/alter tables, delete/edit/add fields, execute any SQL statement, manage keys on fields.

3. ADempiere Bazaar
https://sourceforge.net/projects/adempiere
Adempiere is an ERP Bazaar for Open Source Developers that contribute improvements of Compiere, CRM, Shopfloor, POS, Helpdesk, Financials Accounting, Supply Chain, Knowledge and Business apps in an open and unabated fashion. Focus is on the Community.

4. FreeCol
https://sourceforge.net/projects/freecol
FreeCol is an open version of Colonization. It is a Civilization-like game in which the player has to conquer the new world.

5. FileZilla
https://sourceforge.net/projects/filezilla
FileZilla is a fast FTP and SFTP client for Windows with a lot of features.FileZilla Server is a reliable FTP server.

6. ZK - Simply Ajax
https://sourceforge.net/projects/zk1
ZK is Ajax framework enriching Web apps with little programming. With event-driven components and XUL/XHTML markup languages, developing is as simple as programming desktops and authoring HTML pages. Scripting support Java, JavaScript, Ruby, Groovy...

7. Pidgin
https://sourceforge.net/projects/pidgin
Pidgin is a GTK+ instant messaging application for Windows and Unix. It supports AIM, ICQ, Jabber/XMPP, MSN, Yahoo!, Bonjour, Gadu-Gadu, IRC, QQ, SILC, SIMPLE and more. Seehttp://pidgin.im/about.php for more information.

8. 7-Zip
https://sourceforge.net/projects/sevenzip
7-Zip is a file archiver with the high compression ratio. The program supports 7z, ZIP, CAB, RAR, ARJ, LZH, CHM, GZIP, BZIP2, Z, TAR, CPIO, RPM and DEB formats. Compression ratio in the new 7z format is 30-50% better than ratio in ZIP format.

9. KeePass Password Safe
https://sourceforge.net/projects/keepass
KeePass Password Safe is a free, open source, light-weight and easy-to-use password manager for Windows. You can store your passwords in a highly-encrypted database, which is locked with one master password or key file.

10. XOOPS Dynamic Web CMS
https://sourceforge.net/projects/xoops
XOOPS is a dynamic web content management system written in PHP for the MySQL database. Its object orientation makes it an ideal tool for developing small or large community websites, intra company and corporate portals, weblogs and much more.

11. Arianne RPG
https://sourceforge.net/projects/arianne
Arianne is a multiplayer online engine to develop turn based and real time games providing a simple way of creating the game server rules and clients like Stendhal. Marauroa, our server, uses Java and MySQL for hosting hundreds of players on a solo host.

12. Zenoss Core - Enterprise IT Monitoringhttps://sourceforge.net/projects/zenoss
Zenoss Core is an enterprise network and systems management application written in Python/Zope. Zenoss provides an integrated product for monitoring availability, performance, events and configuration across layers and across platforms.

13. Open Computers and Software Inventoryhttps://sourceforge.net/projects/ocsinventory
OCS Inventory NG, Open Computers and Software Inventory Next Generation is an application designed to help administrator keep track of the computers configuration and installed softwares. Low network traffic HTTP communications between agents and server

14. PhpGedView
https://sourceforge.net/projects/phpgedview
PhpGedView parses GEDCOM 5.5 genealogy files and displays them on the internet in formats and charts that you are familiar with. It also allows relatives to edit their genealogy online and collaborate together on their research.

15. Openbravo ERP
https://sourceforge.net/projects/openbravo
Web based ERP for SMEs, built on proven MVC & MDD framework that facilitate customization & maintenance of code. Already in production, it encompasses a broad range of functionalities such as finance, supply chain, project mgmt, manufacturing & much more

16. Smultron
https://sourceforge.net/projects/smultron
Smultron is a text editor written in Cocoa for Mac OS X 10.4 Tiger which is designed to be both easy to use and powerful.

17. Ares Galaxy
https://sourceforge.net/projects/aresgalaxy
Filesharing-Bittorrent p2p client connected to TCP supernode/leaf network and UDP DHT network. Ares features a built-in directshow media player, a powerful library manager, shoutcast radio support and can be used to host p2p Chatrooms.

18. FreeMind
https://sourceforge.net/projects/freemind
A mind mapper, and at the same time an easy-to-operate hierarchical editor with strong emphasis on folding. These two are not really two different things, just two different descriptions of a single application. Often used for knowledge and content mgmt.

19. Buddi
https://sourceforge.net/projects/buddi
Buddi is a simple budgeting program targeted for users with little or no financial background.It allows users to set up accounts and categories, record transactions, check spending habits, etc.

20. Inkscape
https://sourceforge.net/projects/inkscape
A Linux, Windows & OSX vector graphics editor (SVG format) featuring transparency, gradients, node editing, pattern fills, PNG export, and more. Aiming for capabilities similar to Illustrator, CorelDraw, Visio, etc.

21. MiKTeX
https://sourceforge.net/projects/miktex
MiKTeX is an up-to-date implementation of TeX & Friends for Windows (all current variants).

22. Adaptive Planning Express
https://sourceforge.net/projects/adaptiveplan
Enterprise-class open source business performance management solution that enables companies/departments to move beyond spreadsheets and improve decision making by automating budgeting, forecasting, reporting and analysis.http://www.adaptiveplanning.com

23. PHP For Applications - PHP Frameworkhttps://sourceforge.net/projects/p4a
P4A (PHP For Applications) is a PHP RAD and object oriented PHP framework for building event-driven stateful web applications. Features tableless HTML, accesskey, auto data type recognition, transparent AJAX, UTF-8, i18n/l10n, PEAR integration.

24. opentaps open source ERP+CRM
https://sourceforge.net/projects/opentaps
ERP and CRM suite, including eCommerce, Point-of-Sales, inventory, warehouse, order, customer management, general ledger. Built on OFBiz with enterprise-class features - workflow, databse independence, service-oriented architecture SOA

25. Password Safe
https://sourceforge.net/projects/passwordsafe
Password Safe is a password database utility. Users can keep their passwords securely encrypted on their computers. A single Safe Combination unlocks them all.