Note: This is only a first draft/brainstorm. I will try to organize the list with more useful sections in the future Feel free to contribute!

Download/Scraping utilities

• Rclone: A command line program to sync files and directories to and from various cloud storage providers
• aria2: A lightweight multi-protocol & multi-source command-line download utility
• wget: Utility for non-interactive download of files from the Web (HTTP & FTP)
• curl: Tool and library for transferring data with URL syntax, supporting many protocols
• Youtube-DL: A command-line program to download videos from YouTube and a few hundred more sites
• annie: Youtube-DL alternative writtent in Golang
• wikiteam: set of tools for archiving wikis
• FicSave: Online fanfiction downloader
• FanFicFare: Tool for making eBooks from stories on fanfiction and other web sites
• yt-mango: Youtube metadata archiver
• Youtube-MA: Youtube metadata archiver
• CrowLeer: Powerful C++ web crawler based on libcurl
• floatplane_ripper: Script to rip all videos from https://floatplane.rip/
• grab-site: The archivist's web crawler: WARC output, dashboard for all crawls, dynamic ignore patterns
• dzi-dl: Deep Zoom Image Downloader
• iiif-dl: Command-line tile downloader/assembler for IIIF endpoints/manifests
• ChanThreadWatch: Saves threads from *chan-style boards and checks for updates until the thread dies
• Sonarr: PVR for Usenet and BitTorrent users
• Radarr: A fork of Sonarr to work with movies à la Couchpotato
• Jackett: API support for torrent trackers (works with Sonarr, Radarr and others)
• Sick-Beard: PVR for newsgroup users (with limited torrent support)
• Lidarr: Music collection manager for Usenet and BitTorrent users
• Mylar: An automated Comic Book downloader (cbr/cbz) for use with SABnzbd, NZBGet and torrents
• bazarr: Companion application to Sonarr and Radarr for downloading subtitles
• RipMe: RipMe is an album ripper for various websites. Runs on your computer. Requires Java 8.
• Instagram Scraper: Instagram-scraper is a command-line application written in Python that scrapes and downloads an instagram user's photos and videos. Use responsibly.
• gallery-dl: Fownload image galleries and collections from pixiv, exhentai, danbooru and more
• FlexGet: Multipurpose automation tool for content like torrents, nzbs, podcasts, comics, series, movies, etc
• PyInstaLive: Instagram live stream downloader.
• RedditDownloader: Scrapes Reddit to download media of your choice
• HTTrack: Download a website from the Internet to a local directory
• Heritrix: Extensible, web-scale, archival-quality web crawler
• wail: Web Archiving Integration Layer: One-Click User Instigated Preservation
• Collect: A server to collect & archive websites that also supports video downloads

Compression

• KGB Archiver: compression tool with unbelievable high compression rate
• peazip: File archiver utility

Network

• NetLimiter: Internet traffic control and monitoring tool for Windows

File systems

• NTFS drivers for MacOS
• httpdirfs: A filesystem which allows you to mount HTTP directory listings
• mergerfs: a featureful union filesystem

File conversion

• AAXtoMP3: convert AAX files to common MP3, M4A, M4B, flac and ogg formats through a basic bash script frontend to FFMPEG
• html2warc: Convert web resources to a single warc file

Utility Scripts

• rclone_dirsize: Get size of http directory listing with rclone
• youtube-dl_soundcloud: snippet for using youtube-dl to download soundcloud playlists
• rm_empty_subdir: Remove empty sub-directories on Windows
• void-cat-uploader: This script automatically uploads all files inside a directory to https://void.cat.
• Backblaze B2 sync backup script: Script to sync mutliple directories with Backblaze B2
• Misc download scripts: Scripts for downloading content from various websites

Content sharing

• opds: Easy to use, Open & Decentralized Content Distribution
• ipfs: Protocol and network designed to create a content-addressable, peer-to-peer method of storing and sharing hypermedia in a distributed file system
• h5ai: HTTP web server index for Apache httpd, lighttpd, nginx and Cherokee

Data curation

• DeepSort: AI powered image tagger backed by DeepDetect
• diskover: File system crawler, disk space usage, file search engine and file system analytics powered by Elasticsearch
• fucking-weeb: A library manager for animu (and TV shows, and whatever).
• Everything: Locate files and folders by name instantly (Windows)
• beets: Music library manager and MusicBrainz tagger
• picard: MusicBrainz tagger
• Calibre: Ebook manager
• WinDirStat: Disk usage statistics viewer and cleanup tool for Windows
• jdupes: Powerful duplicate file finder
• Mp3tag: Powerful and easy-to-use tool to edit metadata of audio files (Windows/Mac)
• FileBot: FileBot is the ultimate tool for organizing and renaming your Movies, TV Shows and Anime
• MediaInfo: Convenient unified display of the most relevant technical and tag data for video and audio files
• tree: 'tree' command for linux
• grepWin: A powerful and fast search tool using regular expressions (Windows)
• TeraCopy: Copy your files faster and more securely
• baobab: Graphical disk usage analyzer
• phockup: Media sorting tool to organize photos and videos from your camera
• MediaElch: Media manager for Kodi

APIs & Online tools

• thetvdb: TV shows metadata (used by plex)
• iqdb: Multi-service reverse image search

Hardware / Monitoring

• CrystalDiskInfo: A HDD/SSD utility software which supports a part of USB, Intel RAID and NVMe.
• smartmontools: Control and monitor storage systems using the (SMART) built into most modern ATA/SATA, SCSI/SAS and NVMe disks
• Hard Drive Sentinel: Multi-OS SSD and HDD monitoring and analysis software