Copying of files through the internet or external storage media like USB thumb drives, hard disks etc.
Magic Wormhole – library and command-line tool, which makes it possible to get arbitrary-sized files and directories (or short pieces of text) from one computer to another
File Pizza – Free peer-to-peer file transfers in your browser.
Firefox Send – lets you share files with end-to-end encryption and a link that automatically expires. So you can keep what you share private and make sure your stuff doesn’t stay online forever.
OnionShare – open source tool that lets you securely and anonymously share a file of any size.