> Copying files onto a USB stick requires physical proximity, and is uncomfortable for transferring long-term secrets because flash memory is hard to erase. Copying files with ssh/scp is fine, but requires previous arrangements and an account on the target machine, and how do you bootstrap the account? Copying files through email first requires transcribing an email address in the opposite direction

I had similar motivations in 2006 to write a tool to copy files "point to point". So here's my shameless plug:

https://bitbucket.org/etanol/canute

In my case, cryptography was not a requirement, though.