Brian Warner - Magic Wormhole- Simple Secure File Transfer - PyCon 2016.mp4

I could not find an example on the gibhub page, but here is the timecode from a video that shows it in action: [VIDEO] Also: [LINK] Looks neat.

According to parents nice talk[1] you can add a verify switch that lets you compare the signature of the actual key. So a public authenticated channel is enough. [1] [VIDEO]

Have you taken a look at magic-wormhole[1]? I've started using it recently and it's insanely easy to use. It does have a centralised signalling server for key exchange between peers, but it does attempt to do peer-to-peer data transfer (only falling back to a TURN-style relay if both clients are behind NATs and aren't on the same local network). An explanation of the cryptography and design was given at PyCon 2016[2]. It also has built-in optional Tor support (though I'm not sure if it attempts to use an onion service for data transfer). [1]: [LINK] [2]: [VIDEO]

Here's a link from Brain Warner (the author) talking about that: [VIDEO] Hope it helps, it's a good question.

Magic Wormhole: [LINK] An easy and secure file transfer program. I use it almost everyday since I discovered it. Author has a very good video on it at pycon-2016: [VIDEO]