Interesting, but unnecessary. First, if a private key is protected with a passphrase with sufficient entropy to withstand a sophisticated attack, then even if t

Interesting, but unnecessary. First, if a private key is protected with a passphrase with sufficient entropy to withstand a sophisticated attack, then even if the key is on a USB thumb drive, access to the remote system where the public portion is installed is not compromised. Second, if the key was unprotected on a USB drive, and the drive is lost, what's stopping you from taking the key out of the authorized_keys file on the remote server? Lastly, if there is a need for a single use SSH key, then it should be indicated as such in the key's comment, so when the scenario is over, it's easily identified as which key it is. I guess I don't understand the practicality of this script, let alone one-time SSH keys.