sapereaude

Great post!

BTW, you can also now use hardware devices (like TREZOR and KeepKey) to perform "ssh-agent" functionality in hardware, with minimal setup work.

Blog post: https://medium.com/@satoshilabs/trezor-firmware-1-3-4-enable...

Source code: https://github.com/romanz/trezor-agent (the README has several demo screencasts).

Did you considered to accept Bitcoin payments? This way you wouldn't have to worry about chargebacks.