Linked by Amjith Ramanujam on Sat 14th Feb 2009 02:00 UTC
IanOS is an experimental 64-bit operating system written from scratch as a learning experience. The source code is available online and the creator of the OS has made some detailed documentation available to go with the source code. This is an excellent resource for anyone who wants to venture into writing a 64-bit OS. The author makes his intention about this OS clear "I never had any intention of producing a true OS. There are plenty of those about and it would be a very foolish, or vain, person who thought that they could compete with the likes of FreeBSD and Linux. But my interest in computers isn't practical; I just find programming them, particularly at this level, to be a supremely satisfying intellectual pursuit".