2 Factor Authentication for Linux
From KlavoWiki
Arch Linux
I'll do up a more detailed document but I followed these instruction
https://wiki.archlinux.org/index.php/Google_Authenticator
Install yaourt if not already installed.
pacman -S yaourt
yaourt -S google-authenticator-libpam-git
Note: You will need to edit the build and change the kernel from x686 and x386 to all