Please write a single answer per comment to clearly see the most popular tools. Vote on the ones you like.
There were too many options in this post and I want to see what are the really interesting ones.
To complement this post:
What file-sharing and media organizing software do you wish that existed?
deleted by creator
mldonkey cross-platform multi-network p2p daemon
Tixati is an alternative torrenting program that I switched to from QBitorrent.
Musicbrainz Picard for fetching music metadata and standardizing file naming schemes.
beets music library management and tagging for geeks
digikam for image and video collection management and viewing (also does duplicate detection)
Deluge run headless. Great Android mobile app.
yt-dlp for downloading videos from various websites.
Recently found out about Stacher which is a GUI for yt-dlp
(didn’t see you posted this one as I was posting it)
yt-dlp youtube-dl fork that is more current and works better for tons of sites to download media.
ffmpeg the Swiss army knife for everything video and audio.
Spotiflyer downloads playlists from Spotify and many other services.
rtorrent great to download torrents especially on a server.
mkvtoolnix create/edit mkv files. Very useful to remove or add subtitles or audio tracks amongst others.
aria2 for downloading files.
