SRS is right on the money--keep a buffer supply of the things that you use regularly--with extra emphasis on drinking water(three or more weeks supply, with extra for cooking)--

Even if civilization doesn't end, the power can go out, whether due to a storm or just administrative stupidity--so think about how you're going to cook the food--

It is also worth thinking about how you're heat the place, and how you'll access all that important info you keep on the computer--

Keep in mind that, in times of emergency, gas for that all terrain SUV may be a a little dear.
An old fashioned bicycle basket, which you can make one of the numerous bikes we all seem to have in the garage(and a tire pump), a handy thing for running errands and shopping--

Though some of you seem eager to kill your friends and neighbors at the earliest opportunity--generally, when confronted with catastrophe, people work together--civilization, in the final analysis, does not require technology--it merely requires that people recognize the need to cooperate--