hey, that bear has no pants on!
Bash Scripting for Beginners
Defensive Bash Shell Scripting
Lots of Free Computer Books
Post Scientific Linux 6 Installation Guide
Dell and HP Warranty Lookup Tool
openldap install script
UNIX screen Command
Learn Linux Tutorial
UNIX History Timeline (pdf)
Linux Logical Volume Configurations
HP Raid Controller Command for Linux (hpacucli) (Quick Reference)
vi tutorial

I get asked about topsave all the time. I run it in cron every minute and capture about a week's worth of top output. topsave

Linux LVM (Quick Reference)

These will help you avoid a screensaver in a corporate environment:
MainClass.Java - moves a mouse
MainClass.class - moves a mouse

Beej's Guide to Network Programming
Beej's Guides
admin 1 class
Multipath Devices
foo.cfg (new classroom.cfg)
Linux Performance Tools (by /u/redct on reddit)
New Sysadmin List