Unsure how well known it is, but flameshot (screenshot tool).

I prefer CLI usually, so: zoxide, the zsh git plugin for aliases (e.g.: gst is git status), fzf zsh plugin and the tldr command comes in handy sometimes.

Also, this might be useful just for me, but due to orientation of my living space, I have to fiddle with monitor brightness at least three times a day so I made myself a little Qt tray wrapper around ddcutil’s ddcquery which can change standard vesa monitors brightness/contrast (DDC/CI communication).
There is also ddcui/gddccontrol GUI that does the same thing.

For cli oriented folks, ncdu is a great cli alternative of QDirStat

Yeah Nick (the guy behind this) is one of a kind (in a good way) lol

Also recommend checking out this demo of NotCurses https://www.youtube.com/watch?v=cYhZ7myXyyg it’s great