Sneakernet is an informal term for the transfer of electronic information by physically moving media such as magnetic tape, floppy disks, optical discs, USB flash drives or external hard drives between computers, rather than transmitting it over a computer network. The term, a tongue-in-cheek play on net(work) as in Internet or Ethernet, refers to walking in sneakers as the transport mechanism.
WikipediaYou become a sneaker when you share and send something to someone. Create and name your directory with your pseudo/name.
Fill it with what you want to share : documents, images, videos, music, code...
Don't change other sneakers content.
When your media is full, send it back to the first sneaker.
Accept hardware only from persons you trust.