I like the Foolish People version:
What You Can Do to Prepare:
1) Can you hear the droning sound?
2) Do you or any of your family members have a sharp metallic taste in your mouth?
3) Is the local environment you are inhabiting, your home or shelter becoming less tangible?
4) Are doors or rooms appearing where there were none previously?
--much respect to John Harrigan on that one: http://twitter.com/Johnharrigan