Ubuntu Authenticator can be used for the two factor authentication for Ubuntu SSO and other OATH-TOTP compliant two factor auth sites. It also features easy configuration by scanning QR-Codes using the camera.
Only event based (counter) authentication tokens are supported at present.
Installation packages can be downloaded from the Ubuntu App Store.
Source code at: https://code.launchpad.net/~mzanetti/+junk/ubuntu-authenticator