MasterBooter
Boot manager which can be used to install and maintain operating systems on a PC. Supports many operating systems. Shareware and registered versions available.
http://www.masterbooter.com/

SIGOPS: Operating Systems
Addresses issues dealing with operating systems research and development.
http://www.sigops.org/

DBLP Bibliography: Operating Systems
Links to many operating systems journals on the web.
http://www.informatik.uni-trier.de/~ley/db/os.html

A Catalog of Operating Systems
Classified, alphabetic listing of most operating systems, past and present, distributed commercially or reported in English-language literature, platform oriented. From Computer Science 258, West Virginia University.
http://www.csee.wvu.edu/~jdm/classes/cs258/OScat

MIT LCS Parallel and Distributed Operating Systems
MIT CSAIL Parallel and Distributed Operating Systems homepage
http://pdos.csail.mit.edu/

Easysoft
Operating systems are defined here. All type of operating systems like windows,unix,linux,debian are defined here.open bsd as well as bsd is described here
http://in.geocities.com/easysoft2002/

Operating Systems Through Time (8-bits)
A brief history of 8-bit operating systems.
http://www.armory.com/~spectre/tech.html

CS 3210 Design of Operating Systems
A course in operating systems with a focus on the design and construction of a modern OS kernel.
http://www.cc.gatech.edu/classes/AY2000/cs3210_spring/

Retrospective in Operating System Arts
Documentations on how to get various operating systems running inside Hercules.
http://open360.copyleft.de/

Converting Text Files Between Operating Systems
How to transfer text files between Linux, Macintosh, and Microsoft Windows operating systems, relating to line feed and carriage return characters.
http://www.websiterepairguy.com/articles/os/crlf.html