1. K-Meleon Browser Source Code (C++) - http://sourceforge.net/
K-Meleon is an extremely fast, customizable, lightweight web browser based on the Gecko layout engine developed by Mozilla which is also used by Firefox. K-Meleon isfree, open source software released under the GNU General Public License and is designed specifically for Microsoft Windows (Win32) operating system
2. Amaya Editor/Browser Source Code (C++) - http://www.w3.org/Amaya/User/
Amaya is a Web editor, i.e. a tool used to create and update documents directly on the Web. Browsing features are seamlessly integrated with the editing and remote access features in a uniform environment. This follows the original vision of the Web as a space for collaboration and not just a one-way publishing medium.
3. Shareaza (C++) - http://sourceforge.net/
Shareaza is a multi-network peer-to-peer ( P2P ) file-sharing client supporting Gnutella2, Gnutella, eDonkey2000 ( eMule ), HTTP, FTP and BitTorrent protocols. Using C++, MFC and ATL, for Windows.
4. PAW - Pro Active Webfilte(Java) - http://sourceforge.net/
AW (pro-active webfilter) is an Open-Source filtering HTTP proxy based on the Brazil Framework provided as a Open-Source Project by SUN. Because the Brazil Framework and PAW are written in Java the software is highly portable.
5. ClamWin AntiVirus(C++) - http://sourceforge.net/
Free Antivirus for Windows. Includes virus scanner, scheduler, virus database updates, context menu integration to MS Windows Explorer and Addin to MS Outlook. Also features easy setup program. Uses a well respected ClamAV scanning engine.
6. OpenAV(C#) - http://sourceforge.net/
OpanAV want to build a valid alternative to the commercial products and is based on existing ClamAV and on ClamWinRT technology
7. OpenFirewall(C#) - http://sourceforge.net/
OpenFirewall is based on two lines of defence first WIPFW ( Kernel-mode driver ) and second tdifw ( application-mode TDI-driver ) . Is a Windows firewall easy to use like the commercial products
8. StoneWall -http://sourceforge.net/
This project is fusion of OpenFirewall and OpenAV, so is a complete security system ( firewall protection from tdifw and wipfw project and anivirus from ClamWinRT and ClamAV project ) with OpenUpdate integration
9. tdi_fw( C ) - http://sourceforge.net/
Simple TDI-Based Open Source Personal Firewall for Windows NT4/2000/XP/2003
10. Winpooch Watchdog( C ) - http://sourceforge.net/
Winpooch is a watchdog for Windows (2000, XP, 2003, but only 32-bits). It detects modifications in your system, so as to detect a trojan or a spyware installation. It also includes a real-time anti-virus
11. Spyware Blocke(C++) - http://sourceforge.net/
Open Source spyware remover/detection application for windows.
Polipo is a small and fast caching web proxy. It is typically used as a web proxy for a single computer or a small network. Because it has primitive filtering capabilities, Polipo can be used in place of ad-filtering, privacy-enhancing proxies such as Junkbuster, Privoxy or WWWOFFLE. As Polipo has much more refined HTTP support, it doesn't impose the speed tax usually associated with such proxy.
13. Squid - A caching Web Proxy - http://www.squid-cache.org/
Squid is a caching proxy for the Web supporting HTTP, HTTPS, FTP, and more. It reduces bandwidth and improves response times by caching and reusing frequently-requested web pages. Squid has extensive access controls and makes a great server accelerator. It runs on most available operating systems, including Windows and is licensed under the GNU GPL.
14. Privoxy – A non caching Web Proxy - http://www.privoxy.org/
Privoxy is a non-caching web proxy with advanced filtering capabilities for enhancing privacy, modifying web page data and HTTP headers, controlling access, and removing ads and other obnoxious Internet junk. Privoxy has a flexible configuration and can be customized to suit individual needs and tastes. It has application for both stand-alone systems and multi-user network
15. Open Source Firewall Projects - http://osswin.sourceforge.net/#firewall
16. Automatic Software Update - http://sourceforge.net/projects/asu-service/
17. Brute Force Grid - http://sourceforge.net/projects/bruteforcegrid/