Most of the time you access Linux machines you'll use SSH with a private key. You add your public key to
~/.ssh/authorized_keys and done, you can login using your private key and passphrase.
To serve HTTPS traffic, you use your private key to create a certificate signing request. You submit the request to a certificate authority and receive a certificate in return. The certificate is basically a stamp of approval on your private key.
Today I noticed that the certificate authority I use (http://startssl.com/) also acts as an OpenID provider. If I log on to Stack Overflow using
https://yourname.startssl.com, I can log on using just my private key, just like an SSH server.
It seems really easy to use. One time import of the certificate, and no need to remember the password unless you reinstall the machine.
Is this way of logging on a good idea?