What I use

Software

Calculator: calc.
Calendar: calcurse.
Debugging/tracing: GDB, DTrace.
Digital audio workstation (DAW): Ardour.
Document formatting: Plain text, Markdown, LaTeX.
Document viewer: zathura.
Dotfile manager: stow.
Email client: NeoMutt with isync.
Expense tracking: fnc.
File manager: None.
Filesystem: ZFS.
Fuzzy searching: dmenu and fzf.
IRC: Irssi.
Image editing: ImageMagick for simple things and conversions, Gimp for more complicated edits.
Image viewer: nsxiv.
Instant messaging: Signal.
Monero wallet: Official CLI wallet.
Music player: cmus.
My scripts.
Notifications: nfy.
Operating system: FreeBSD on the desktop, OpenBSD on the server. Occasionally playing around with 9front.
Password manager: pass.
Presentations: LaTeX Beamer for proper presentations, sent for simple ones.
RSS reader: sfeed.
Screen locking: slock.
Screenshots: scrot.
Shell: sh(1).
Sound system: FreeBSD’s OSS, sometimes with virtual_oss.
Spreadsheets: LibreOffice
Static site generator: Hugo.
Syncing: rsync.
Terminal: st with tmux.
Text editor: Neovim. I also like Acme.
Downloading: ~~qBittorrent, Nicotine+, yt-dlp.~~ That’s illegal!
Version control: Git.
Video player: mpv.
Video/audio manipulation and recording: FFmpeg.
Virtualization: FreeBSD’s bhyve(8) and occasionally QEMU.
Web browser: LibreWolf with arkenfox/user.js, uBlock, Decentraleyes, I still don’t care about cookies, Vim Vixen.
Window manager: dwm with slstatus.
The rest: Standard UNIX/BSD utilities.