After listening to Mac Power Users #173 I decided to repurpose a USB key I had on my keychain into a 1password emergency data store.
There's only one problem with this. Browsers have recently been locking down "local" file access, so the normal method of opening up the 1password.html file in Safari doesn't work. You'll know it doesn't work when you get this screen
This is happening because Safari can't read the encryptionKeys.js file from the local disk.
However, this is easily fixed by turning on the Develop menu in Safari
And then checking off "Disable Local File Restrictions" in the Develop menu.