fish: Documentation
Manual for the fish shell. I'm very tempted to give this a try out with a view to changing from zsh.
What The @#$%&! (Heck) is this #! (Hash-Bang) Thingy In My Bash Script | Linux Journal
Handy article to help explain shebang to people.
Advanced Bash-Scripting Guide
And advanced guide to bash scripting.
tildeverse
It looks like free shell accounts are still a thing, and there's a movement to encourage their use. Which is kinda cool.
Colorize your CLI
Blog post that documents some different ways, and some useful tools, for giving more colour to the CLI.
Build your own NeXT with a virtual machine
Instructions on getting a NeXT machine up and running in a VM.
.plan
Online plan/finger site, which actually supports finger. Actually really rather neat.
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.