There are a million bajillion different ways to transfer files between computers, but each seems to have its own quirks that make it not quite the right solution for the particular use case. This is especially the case when transferring sensitive data like passwords, API keys, etc.

Magic Wormhole seems to be a really well thought out solution to this problem. It offers a secure medium (using password-authenticated key exchange) while also managing to have a super easy to use CLI. Just wormhole send secrets.txt, tell your friend the magic code (something like 3-cake-ambiguous), and they can receive it by running wormhole receive. Super elegant!