Linux

Rsync for moving files and backing up.

• xournal for fake form-filling on PDFs - ugly and unintuitive but gets the job done
• img2pdf - does what it says on the tin
• ranger for managing files and launching stuff - not the coolest kid on the block but this is the single most impressive terminal app I have used in recent years, the key bindings and commands and defaults are so crazily intuitive that I hardly ever even need to consult the manual

find -exec is essential to process multiple files

7z handles wildcards inside a find -exec so you can save 200 lines of sh compliance

mpv plays online media since it uses yt-dlp

I use:

• qpdf for mucking around with pdfs, reordering, selecting pages, combining them, etc.
• ffmpeg for video and audio sicing and transcoding. Usually encompassing a command in a script because I forget the precise params every time ;p
• nvim for anything like Markdown (which can be converted to other things like LaTeX or pdf or html, sometimes in multiple stages)
• imagemagick for simple image conversion stuff.
• wget for downloads ^.^
• youtube-dl or yt-dlp for grabbing youtube stuff.

I use most of these that you listed, except that I don't use office apps at all, and do all my documents using LaTeX in neovim.

Also, I have small helper scrips for pdf manipulation for tasks that I do regularly, like making my handwritten notes ready for printing at my office since I don't like the algo my office printer uses to convert them to B&W. I also use sejda-console for merging PDFs as it has nice options for manipulating TOC during the merge.

Another nice utility is ffpb which is basically a wrapper around ffmpeg that gives it a nice progress bar.

Aria2c is the best downloader for large files. It also supports torrents.

You can also use ghostscript (gs) or the image magick convert with PDF.

I use rsync quite often and ssh as well.

• pdfcrop (commonly included with LaTeX) for cropping margins - it cuts the pdf down to its contents then adds a margin of your choosing, extremely useful for forcing academic papers to have consistent margins, pdfcrop --margins 72 *pdf here* will create a document with a ~1in margin all around (it uses bp as its units)
• vips for resizing/converting images - it's a bit faster and lighter than imagemagick in my experience, although the main reason I use it instead of imagemagick is just because I like playing around with stuff I haven't used before :) It has an officially supported python binding too

I'd add:

• ghostscript - with some basic perl scripts, works great for pdf flattening/compressing, merging, splitting, adding bookmarks etc.
• poppler - pdfseparate, sometimes pdfunite
• zathura - pdf viewing
• feh - images
• sshfs - prefer it to rclone
• cheat
• emacs - org-mode, latex, dired/wdired, capture, eshell, vterm, tramp
• mc/midnight commander

https://github.com/WyattBlue/auto-editor - automatically editing video and audio by analyzing a variety of methods, most notably audio loudness

https://github.com/shssoichiro/oxipng, https://pngquant.org/ and https://github.com/RazrFalcon/svgcleaner for optimizing images

For audio files sox and beets are my live saver.

I download files with axel

Using lf, a file manager like ranger. Written in Go.

https://github.com/gokcehan/lf

@antihero I use ffmpeg to extract frames from images. Yt-dlp to download youtube videos. Rmlint, to remove duplicates. Gallery-dl to sometimes download from sites like instagram or twitter & finally mpd / ncmpcpp to listen to music....

syncthing to sync my files on all my devices

• convert - convert between image formats as well as resize an image, blur, crop, despeckle, dither, draw on, flip, join, re-sample, etc. Almost nothing it can't do.