Andalus is an x86 based OS kernel
A operating system designed to be compatable with the linux and uinx software, that is capable of running as a modern operating system.
This is an OS kernel for arm920t platform.
ArchOpen is a project aimed at providing a fast, light and free operating system and applications for portable multimedia devices based on TI DM&DSC chips. It currently supports a lot of Archos multimedia devices (Gmini402,AV400,...).
Handix is the OS for the Aura line of simple, inexpensive palmtop-type handhelds, designed by this project.
Aurora OS is an operating system designed in a microkernel format for all users. The object is to develop a modular, mulitplatform, multitasking Operating System that is simple, effective, and powerful.
BOS – B.lu operating System, is an operating system dedicated to small microcontrollers and CPUs without MMU. Actually is dedicated to Texas Instruments MSP430 microcontrollers (it can be ported to other CPUs without great changes)
BNL OS is a free, modern operating system based on the design of Windows XP/2003.This is not a Linux based system, and shares none of the unix architecture. Please remember, this is in the development stage, and is not reccommended for everyday use.
fast single-privilege single-address-space preemptive-multithreading persistent data-centric secure multiuser operating system with safe-language and reconfigurable graphical interface
The Banana Kernel is an open-source pedagogical operating system intended to provide useful means for teaching basic OS concepts, with the possibility of interaction with external modules developed by the teacher or student.
Barbux, the bearded people OS
Hobbyist operating system using a new microkernel. The objective is to not get bogged down by ancient legacy processor support. The OS is meant to be designed from the ground up, without utilizing any legacy or existing implementations or designs.
Blueport is an italian Open Source 32-bit operating system ... This project has temporarly moved to Gna.org: <a href="http://gna.org/projects/blueport">Blueport project</a>
CJet eXTreme OS is a new project to develop a cross platform operating system with a native application interface designed to make it easy to develop for several architectures at once.
COS - Component-based Operating System
CakeOS is a hobby operating system started by Lukem_95. It is written in C with some partial ASM coding. Cake is a modern OS with portable functions and drivers. We are looking to keep a fairly small team size for this project.
Caracal is an IA32 operating system which, once stable, will be used to create tutorials and therefore teach others the basics of writing system software for IA32 processors.
Caracal Boot Loader (cboot) is a second stage boot loader which takes over from GRUB (or other multiboot compatible loader) and prepares the system for your higher-half kernel. It now also includes VESA mode setting support.
This project is meant to increase the efficiency of Linux kernel 188.8.131.52 in cell Broadband Engine.This is in accordance to the IBM cell BE challenge-2.
Cellocity Linux is Based on Fedora Core 6 Source Code. With only basic core elements needed to operate Compatipal and a completley Graphic Interface as well as Text. Version 2.0 will include more applications 32,64 bit and 80 Core Intel CPU
Cerberus is an attempt at creating flexible and extremely customizable Operating System that can be used on many types of computer systems including desktops, servers, and embedded solutions.
A (new), Distributed and Supercomuting ready, Component Oriented Opperating System, together with a (special) toolchain to build it. (It will run on I386 networked machines initially)
CleanOS is an operating system developed for educational purposes, initially to be an userspace GNU/Linux application running its executables and simulating the operating system task scheduler and IPC mechanisms. Now it supports a true i386 kernel.
The CodeTime platform covers every aspect of parallel software from authoring, through distribution, to run-time. Its goals are: high programmer productivity; write once, run high performance anywhere; and wide acceptance.
Coremark is hardware performance & analysis platform. Coremark is built-on it's own specific kernel allowing stable performance results and direct access to hardware.