Turn almost any device into a file server with resumable uploads/downloads using any web browser.

Firefiles is an open-source alternative to Dropbox that lets you manage files across multiple cloud storage providers through a single interface.

qrcp is a command line tool to transfer files from a desktop to a mobile device (and the other way around) over Wi-Fi, by scanning a QR code. It's available for Microsoft Windows, macOS and Linux.

Downloads videos from YouTube and some other sites; useful for automated bulk downloads.

aims to be a "easy-to-use and unbloated client for the UNIX and UNIX-like console".

Synchronizes a local copy of a website with a remote copy on a server; does not use SSH/scp but FTP for file copy; useful when the remote server does not support secure copy.

Mirror directories across networked machines; handles diffs/changed files; works across SSH; plenty of parameters.

"An open source tool that lets you securely and anonymously share a file of any size."

The program allows transfer arbitrary-sized files and directories (or short pieces of text) from one computer to another.

The two endpoints are identified by using identical human-readable codes.

"Sophisticated ftp/http client, and a file transfer program supporting a number of network protocols"; support for bookmarks and mirroring features.

A lightweight, Free Software, cross-platform BitTorrent client; a terminal curses interface, web interface and command line client can connect to a running daemon to manage torrent downloads.

A tool and library for transferring data with URL syntax; supports a lot of protocols.

Lightweight and easy-to-use download utility; it supports HTTP/HTTPS, FTP, SFTP, BitTorrent, Metalink and multiple sources; cross-platform.

Full featured and highly configurable SFTP server software.

Sia is a decentralized storage platform secured by blockchain technology. The Sia Storage Platform leverages underutilized hard drive capacity around the world to create a data storage marketplace that is more reliable and lower cost than traditional cloud storage providers.

Firefox Send, send.firefox.com, is a free encrypted file transfer service that allows users to safely and simply share files from any browser.