Yubikeys have been added as a method of two factor authentication.
Currently supported are standard yubikeys (ordered from Yubico).
We will add support for MtGox Yubikeys once I get the key in the post.
If you are using GLBSE and have a Yubikey, I advise enabling two factor authentication for everything.
MtGox Yubikeys support. thumbs up.
Now I don't have to order multiple Yubikeys.