1. Gnu.org
Sign up for the Free Software Supporter A monthly update on GNU and the FSF Richard Stallman announced in September 1983 the plan to develop a free software Unix-like operating system called GNU. GNU is the only operating system developed specifically for
http://www.gnu.org

2. Landesk.com It-management-software Page
http://www.landesk.com/it-management-software.aspx

3. Klocwork.com
Security, software reliability and regulatory compliance are significant factors for developers of Safety-Critical Embedded Systems Software. Klocwork assists with meeting these requirements through enforcement of coding standards, early prevention of
http://www.klocwork.com

4. Eros-os.org
EROS: The Extremely Reliable Operating System The EROS research effort has ended. Work is continuing from the EROS code base in the CapROS project, which is led by Charlie Landau. There are also some commercial collaborations that are building on EROS and
http://www.eros-os.org

5. Debian.org
Debian GNU/Linux is a free distribution of the GNU/Linux operating system. It is maintained and updated through the work of many users who volunteer their time and effort.
http://www.debian.org

6. Srom.zgp.org
The operating system quality and approval metric
http://srom.zgp.org

7. Freebsd.org
The FreeBSD Project
http://www.freebsd.org

8. Haiku-os.org
Haiku is an open source desktop operating system currently under development inspired by the BeOS. Haiku aims to provide users of all levels with a personal computing experience that is simple yet powerful, and free of any unnecessary complexities.
http://haiku-os.org

9. Linux.com
A Means to World Liberation! Our goal is to provide all the information necessary to make your use of Linux a success.
http://www.linux.com

10. Yoper.com
Yoper: high performance Linux Desktop Operating System. Compact and very fast. i686 optimized.
http://www.yoper.com