Everyone should have an authenticator. Blizzard sells them cheap. Most mobile phones can download them for free for World of Warcraft.
What people don’t think about is their WTF folder. If something goes wrong with your computer your entire UI is gone with that WTF folder. My solution is to use Dropbox along with a trick called junctions or symbolic links. Even if the computer dies, your WoW settings and UI will remain intact. As soon as WoW writes to your hard drive Dropbox starts uploading it to their servers immediately. Also works great if you play wow across multiple machines and want an up-to-date UI flowing seamlessly between them.
I’ll give an example of the command I use for the junctions inside a DOS Command box:
mklink /D “C:\World of Warcraft\WTF\Account\Defective” “C:\Users\Defective\Dropbox\World of Warcraft\WTF\Account\Defective”