"Here's how I turned an unused PC into a packet-filtering firewall using a package called floppyfw. The firewall boots off a single floppy, runs completely in RAM, and uses ipchains for the filter rules. It also does IP masquerading, port forwarding, and can log to a remote host using syslog. All this in a machine with as little as 8 MB of RAM and no hard drive!"

pdowner asks: "I've just finished and handed in my latest Operating Systems Inmternals assignment for my degree in Computer Studies. It

involved writing/modifying a timer module for a Microkernel implemented in modula 2, which is written by one of my lectures and is

available from here. I am interested in finding out what microkernels other universities use to teach their students the insides of Operating

Systems."

Kerneltrap (http://www.kerneltrap.com/) is a news and discussion

portal devoted to low-level systems programming, embedded

systems, and OS kernel hacking. Whether you are a professionally

trained software engineer, a kernel hacking guru, or a weekend

hobbiest with a knack for device drivers, this site should be of

interest to you.

RAID, short for Redundant Array of Inexpensive Disks, is a method whereby information is spread

across several disks, using techniques such as disk striping (RAID Level 0) and disk mirroring (RAID

level 1) to achieve redundancy, lower latency and/or higher bandwidth for reading and/or writing, and

recoverability from hard-disk crashes.

This is the most up-to-date and active Minix website that can be found on the web. It is maintained by Al Woodhull who co-wrote the second edition of the "Operating Systems: Design and Implementation" book with Minix's original author.

This site is dedicated to Mobile UniX systems. It leads you to a lot of useful hands-on information about installing and running Linux and BSD on laptops, PDAs and other mobile computer devices.

The Linux On Laptops Web page was started by to help solve many notebook nightmares. This site, and its various mirrors, serve as a storehouse of Linux experiences with dozens, if not hundreds, of mobile computers.

The Unofficial Mandrake Linux page provides clear, step-by-step instructions for performing a variety of tasks on your Mandrake system, like setting up ethernet, installing rpms and tarballs, and compiling source code.

This is not just a Linux site. There are Linux tutorials and articles here. There are also good links here for PHP, MySQL and pointers to a lot of online resources.

This is a good site for updated news about FreeDOS programs. There's also some good helper programs for FreeDOS written by the maintainer of this site.