Hmm...
My .bash_history is 90% yt-dlp calls and various ffmpeg invocations. gifski has been super useful for making .gif files that don't suck, too.

One thing I found that was useful was (is this a bashism? oh well):
comm <(sort file1) <(sort file2)
This was me checking a script full of video URLs to download against another one to see if I had any duplicates between them. With some more fiddling, I was easily able to generate one big script that didn't have any dupes thanks to comm.

I've used qrencode so I don't have to retype a long/ugly URL from my desktop onto my phone, I can just scan it:
qrencode -t ansi "https://www.youtube.com/watch?v=iNkfGHrXixo"

detox unfucks filenames to make them shell friendly. Love it.
Don't blindly run "detox *" in a directory, lol.

I also do have an actual usecase for cmatrix (which just shows a cool matrix screensaver in the terminal), since it's very useful as a live indicator for your connection quality over SSH.
Several of my machines on the wifi will just suffer and die horribly with 1000ms+ pings, although really, I should just go fucking set them up on a hard-wired network.
It also just looks cool.

...god, that is a LOT of yt-dlp and ffmpeg calls.