I've written more shell scripts than I can count, but I still stumble upon tricks that honestly blow my mind far too often than I care to admit. Latest thing that blew my head clean off? The shell colon.

Tie::File - When Your Array IS the File - Esoteric Ruby programming tutorial from perl.gg

Everyone tells you to use a three-argument open(), but there's a lot more you can do ...

When your data file is the program

The Backtick Heredoc - Esoteric Ruby programming tutorial from perl.gg

Creates a video from an audio file showing an 8-band spectrum analyzer

Put that script inside a folder, share the folder with someone via Syncthing or Dropbox or whatever,

capscreen is a shell script for screen recording on OpenBSD using ffmpeg(1).  It captures the screen and microphone, and optionally overlays a webcam video feed in the top-right corner.