If your threat model predicts a high probability of nuclear war, civilization-threatening pandemics, or other end-of-the-world-as-we-know-it scenarios, you should probably move to a defensible rural homestead with solar panels, a long growing season, and a fresh water supply -- that's an hour away from the nearest interstate. I hear the intermountain west is nice this time of year.
What's interesting is that few prepper/survivalist discussions -- that I've seen, maybe I'm missing them -- mention the opportunity costs of moving to the backwoods. I interviewed Y2K prepper/survivalists who quit their jobs and followed approximately the above advice. The problem arises when the collapse, well, doesn't happen. And you're two hours (in the summer) and six hours (in the winter) from the nearest emergency room.
Also once you sell that city condo or suburban house and move to your self-sufficient rural homestead, you then have a strong incentive to predict the collapse is coming. Maybe it's not going to be Y2K after all, but how about suitcase nukes in big cities? Or bioterror? Etc. There's also a subset of religious survivalists who seem to want an ungodly and immoral secular society to meet its doom; I wrote about this for Wired here: http://archive.wired.com/culture/lifestyle/news/1999/01/1719...