We live in unstable times and who knows what's around the corner? Natural disaster, man-made disaster, terrorism, riots... What might next year bring? What might next week bring? The American Red Cross has long recommended every household have enough supplies to be self-sufficient for several days' duration, and while, yes, I have made the joke that it's easier to store bullets and go take my neighbors' food, well, I can't see myself really plugging old Mr. Glenn in the head over his cans of beans 'n weenies. So, assuming you're not one of those already laying supplies back, this is a good link with some valuable suggestions.
http://www.redcross.org/SERVICES/disaster/beprepared/foodwtr.html