Distributions

LinuxISO - Fresh ISOs, just like Mom used to burn them!

SENTINIX is a GNU/Linux distribution designed for monitoring, intrusion detection, penetration testing, auditing, statistics/graphing and anti-spam. It's completely free; free to use, free to modify and free to distribute. SENTINIX includes the following software, installed and pre-configured; Nagios, Nagat, Snort, SnortCenter, ACID, Cacti, RRDTool, Nessus, Postfix, MailScanner, SpamAssassin, openMosix, MySQL, Apache, PHP, Perl, Python and lots more.

Helix is an Incident Response & Computer Forensics Live CD by e-fense™, Inc.

EduBuntu
"Ubuntu" is an ancient African word, meaning "humanity to others". The Edubuntu Linux distribution brings the spirit of Ubuntu to schools, through its customised school environment.

RPMs

EdWin's RPM Center

FreshRPMs - simple, clean RPM packages

RPM Search

Applications

OpenOffice - a multi-platform office productivity suite

The Gimp - The Gnu Image Manipulation Program

Lamp - how MySQL is used in conjunction with Linux, Apache, and either Perl, Python, or PHP.

PERL, PHP, & SQL
(oh my!)

mySQL

O'Reilly Perl

PHP.net

PostgreSQL

The phpMyAdmin project

Tools

BitDefender - Secure your every bit!

Ethereal - The world's most popular network protocol analyzer

Multi Router Traffic Grapher (MRTG) - monitor the traffic load

OpenXtra - Network management for all

Snort - The Open Source Network Intrusion Detection System

WebMin - web-based interface for system administration

Bacula - The Network Backup Solution

Documentation & HOWTOs  

K12Linux Network Administration Course

O'Reilly

LinuxDevCenter

Introduction To Linux - A Hands On Guide

General Info