Benchmarking BSD and Linux - Compares FreeBSD 5.1, NetBSD 1.6.1, OpenBSD 3.4; Linux 2.4, 2.5, 2.6; to see how scalable and fast network programs are on standard PC hardware as Web servers; tests several APIs and methods. Text, graphs, benchmark code. - http://bulk.fefe.de/scalability/
Linux and BSD, Open Source Giants - Succinct, clear, non-technical introduction to Linux and BSD, focus: how they are relevant to business. - http://shearer.org/en/writing/whatarelinuxbsd.html
PIOS: Pleasant Interactive Operating System - Free Unix clone developed by PIE Software Inc., for x86 PC compatibles, to give a stable multi-user high security platform for use as a network server, programming work-horse, or desktop system; designed so even complex tasks are easy. - http://www.piesoftwareinc.co.uk/
COTSE-Mini Unix Distributions - Links to 2 dozen mini Unix distributions: mostly Linux, also FreeBSD, SCO, Solaris MINIX, MINIX. - http://www.cotse.com/miniunix.htm
Open Source Unix and Related Software Projects - Small page of logos and links to resources, distribution channels for the most popular, freely distributable Unix, and a few other projects. FREENIX links in English, Français, Norsk. - http://www.opensourceunix.com/
ACM Crossroads: Operating Freely - Description of the 3 major, freely available, Unix-like operating systems: Linux, FreeBSD, NetBSD. Crossroads is the student magazine of the ACM. - http://www.acm.org/crossroads/xrds1-3/free.html