The TTY demystified
Some history and details about terminals, their history and their working. Likely very useful for people who haven't encountered actual terminal hardware.
Advanced Bash-Scripting Guide
And advanced guide to bash scripting.
What The @#$%&! (Heck) is this #! (Hash-Bang) Thingy In My Bash Script | Linux Journal
Handy article to help explain shebang to people.