What about water? From the NYTimes story about preparing for the imminent collapse of civilization:
“Your safe haven must be self-sufficient and capable of growing some kind of food,” Mr. Biggs writes. “It should be well-stocked with seed, fertilizer, canned food, wine, medicine, clothes, etc.”
Of course the Times puts coverage of potential societal collapse due to peak oil and/or economic meltdown in the Styles section (or so I’m gathering from the URL of the article).