I agree with all the above. I would like to add that a better investment then gold would be junk silver coins and bullets. If the banking system is down for 3 months it ain't gonna come back. Having enough food to last for a minimum of 6 months per person is vital. After that you can grow a garden and start hunting (or start hunting and gardening to supplement the food stuffs). Buy seeds that are not genetically altered. As many as possible, they don't take up much space and will keep practically forever if they are kept dry.

Bullets, guns, and any tool that would be used on a daily basis will be the currency of the revolution.