Free multiple operating systems software for linux

SmoothWall Express is an open source firewall distribution based on the GNU/Linux operating system.
Linux is the ideal choice for security systems; it is well proven, secure, highly configurable and freely available as open source code.
SmoothWall includes a hardened subset of the GNU/Linux operating system, so you dont have to install any separate OS.
Designed for ease of use, SmoothWall is configured via a web-based GUI, and requires absolutely no knowledge of Linux to install or use.

ROCKate is a LiveCD, a complete operating system that operates without installing it on a harddisk. It focuses on giving people a chance to protect their privacy on the Internet. The LiveCD achieves this goal by using the Tor network for anonymity and delivers all applications pre-configured to use it.
Main features:
- Privoxy/Tor for access to the Tor network
- Xorg for a Graphical User Interface
- IceWM as Window Manager
- dillo as webbrowser
- irssi as IRC Client
ROCKate not only focuses on making it possible to be anonymous on the Internet, it also aims to make it convenient.
Every file on the filesystem is writable! This distincts ROCKate from most other LiveCD systems. This goal is achieved by using Clifford Wolfs shadowfs. The limit to this is the amount of RAM you have in your system.
Enhancements:
- The distribution is now installable to harddisk!

Syllable was born in July 2002 as a fork of the AtheOS operating system. Several AtheOS developers, concerned about the long-term development of AtheOS, created Syllable to ensure that development would continue.
Syllables goal is to create a reliable and easy-to-use open source operating system for the home and small office user. We also want to encourage developers to create an operating system that is intuitive, easy to use, and powerful.
Main features:
- Booting usually takes less than ten seconds
- A full GUI is built into the OS
- Support for a wide range of common hardware devices, including video, network, and sound cards from manufacturers such as Intel, AMD, 3Com, nVidia, and Creative (see Azaka for a complete list)
- Internet access through an Ethernet network (though PPP and PPPoE are not yet supported)
- A graphical web browser (ABrowse) and e-mail client (Whisper), and hundreds of other native applications (see Kamidake for a complete list)
- A journalled file system, modelled on the BeOS file system
- An application launcher (like the Windows Start button)
- 99% POSIX compliance
- GUI-based preferences tools for networking, display preferences, user administration, etc.
- The entire source is available via the GPL
- An object-oriented programming API

eyeOS is a free, cross-platform Personal Content Manager System based upon the style of a Desktop Operating System.

The base package includes the whole Operating System structure and ten apps, as a Calendar, a File Manager, a Text Editor, an Internal Messenger, a Browser and a Calculator.

eyeOSs is thought to provide a complete, scalable and free (GPL Licensed) Organization and Work System.

Easy and powerful Free CMS - eyeOS. eyeOS is scalable, so everyone can port an existing PHP app to eyeOS and create a meta-package for installing it.

Roadnav is an in-car navigation system that can run on a variety of operating systems like Linux, Windows, and Mac OS X.
Roadnav can obtain a cars present location from a GPS unit, plot street maps of the area, and provide verbal turn by turn directions to any location in the USA.
Roadnav uses the free TIGER/Line files from the US Census Bureau to build the maps, along with the GNIS state and topical gazetteer data from the USGS to identify locations.
Main features:
- Generates street level maps for the US
- Interfaces with GPS units to display your position in real time
- Verbal turn by turn directions to any place in the US. Automatically recomputes directions if you miss a turn.
- On screen keyboard
- 3D (drivers perspective) view mode
- Daytime and nighttime color schemes
- Automatic day/night mode switching
- Plots nearby landmarks and points of interest
- Can operate offline (without an Internet connection)
- Antialiased output
- Supports multiple operating systems including Windows, Linux, and Mac OS X
- Uses freely available data from the US Census Bureau and the USGS
- Appearance can be customized with skins
- Can output status information to LCD devices through LCDproc
Enhancements:
Enhancements:
- Adds option to Preferences to enable gpsd buffering (reduces jitter).
- Adds experimental GPX import support.
- Disk usage reduced by ~30%.
- Adds GPS serial initialization string option to Preferences.
- Adds preference to override default map directory.
- Adds option for username/password proxy authentication.
- Adds "Use System Proxy Settings" preference, which reads proxy settings from the HTTP_PROXY environmental variable.
Bug Fixes:
- Fixes Delete button in Waypoints dialog when no waypoints exist.
- Workaround for buggy serial implementations.
- Fixes Windows 2000 compatibility.
- Fixes i18n issue in OSM code.
- Improved address look up.
- Eliminates IPP error messages when printer is not configured.
- Improved compatibility with DeLorme Tripmate and Earthmate GPS units.
- Win32 floating point model changed from fast to precise. Should resolve problems calculating routes.
- Fixes focusing issue in keyboard dialog.
Developer Visible Changes:
- MapControlData_Tiles index files eliminated.
- Direct access to Point::m_fLong and Point::m_fLat eliminated. Use the Point::Set* and Point::Get* functions instead.
Misc:
- Compiled maps now organized in a more human readable format.
- Eliminates TIGER/Line 2006 First Edition from search path.
- Proxy settings now on their own preferences page.
- When maps have to be upgraded, adds option to not upgrade map files and immediately terminate Roadnav instead.
- Small map labels now have a solid background instead of a cross hatch.

The Prex project is an open source initiative to provide a portable real-time operating system for embedded systems.
This project originally started to make a royalty-free OS for mobile phones and PDA in order to spread open source movement to such proprietary OS field. And now, the project target has been shifted to the wider area of real-time and embedded systems.
Prex is designed specifically for small memory footprint platforms. It is written in C language based on traditional micro-kernel architecture. The Prex kernel provides only fundamental features for task, thread, memory, ipc, exception, and synchronization.
The other basic OS functions, process, file system, application loading, and networking, are provided by the user mode servers. In addition, Prex provides a POSIX emulation layer in order to reuse the existing applications.
Prex is an open source royalty-free OS for mobile phones and PDA.
This design allows system to perform both of the native real-time task and the generic *NIX process simultaneously without degrading the real-time performance. Furthermore, it helps the platform designer to construct OS by choosing suitable server tasks for their target requisition.
Prex is royalty-free software released under BSD License
Main features:
- Task and thread control: preemptive priority scheduling with 256 priority levels
- Memory management: virtual address mapping, shared memory, memory protection, with MMU
- IPC: synchronous message passing among threads, object name space in kernel
- Exception: framework for POSIX signal emulation
- Synchronization: semaphores, condition variables, and mutexes with priority inheritance
- Timers: sleep timers, alarm timers
- Interrupt: nested interrupt service routines, and prioritized interrupt service threads
- Device I/O: minimum synchronous I/O interface
- Real-time: low interrupt latency, high resolution timers, periodic timers, and scheduling quantum control
- Cross platform portability: well defined architecture dependent layer and driver-kernel interface
- Modular design: OS servers and BSP module separated from kernel
- Small memory footprint: kernel size < 25k bytes
- Low power consumption: control of processor idle state, support of DVS (Dynamic Voltage Scaling)
- Disk-less: on-core kernel, no memory page swapping
- Instantly available: minimal OS boot time, system suspend/resume, kernel warm restart
- File systems: VFS framework, RAM/FAT/Flash file systems optimized for embedded systems
- Networking: TCP/IP stack, BSD socket interface
- POSIX emulation: signal, process, file I/O, real-time extensions, pthread, etc
- Debug: event logging, GDB remote debug
Enhancements:
- A file system server was added. arfs, devfs, and ramfs are supported with this version.