What's related...

Operating Systems

First of all, some links to collections of OS references. Following these links, you can find any existing OS:

Christopher Browne's Web Page on Research and Experimental Operating Systems
Tune's Review of Operating Systems

If you are interested in the OSLib approach and you are searching for similar projects, then look the Flux OS Toolkit, very similar to our OSLib (see our Project Overview for a deeper comparison). The Pebble project at Bell Labs can also be considered similar to OSLib or to the Flux OS Toolkit, being a toolkit for building component-based Operating Systems.
If you want to create a your own operating system, look at the SigOps page about it.

Some vertically structured OSs:

The Nemesis kernel
The ExoKernel

Some microkernels:

The Mach 4 microkernel
The RT-Mach microkernel
The Fiasco second generation microkernel

...And, of course, the FreeDOS project.

The SHARK kernel is based on a preliminary version of OSLib.

Programming

First of all, a good C/Unix course; links to other programming sites are coming soon.

Philosophy

Here, you will find some links about free software and related arguments. The most important is the GNU Philosophy Page. Another interesting site is the Open Source Page.