Weather, loss of public utilities due to weather or other, public unrest (read riot) for whatever reason, injuries (to myself or others), bad guys in general.

We live full time in our motorhome, traveling the western US doing volunteer camp hosting to help with expenses. That probably gives us a head start over some, 'cuz we always have probably two weeks worth of food on board, 100 gals of fresh water, empty holding tanks (or near so, we dump whenever we can), a built in generator, six house batteries, solar panels to help keep them charged, a large built in propane tank, and a carry around bottle that we run off of when stopped, keeping the built in as full as possible at all times. Lots of blankets, and all season clothing, including rain gear. We have chains for it, a shovel, axe, hatchet, saw, rope, tow strap, full set of wrenches and sockets, the usual pliers and screwdrivers, etc, a set of spare hoses and belts, two fire extinguisers, and I don't recall what else. We never let the gas guage get below half (on either vehicle).

In the little 4WD SUV we tow is our tent camping gear, three person three season tent, two mummy bags, pads, lantern, axe, saw, etc, two+ days worth of food, a single burner stove with fuel, about three gal of water, two sets of chains, tools and parts similar to the ones in the RV, and a portable air compressor capable of inflating the big RV tires to 100+psi in a short time. Fire extinguiser.

CB radio built in to each vehicle, 1000 channel multi band scanner, set of FRS radios, solar/battery/crank multi band (including weather) radio. DVD/VHS player with a couple hundred DVD's.

We keep a shotgun in the RV, and as a retired LEO with HR218 card, I can carry my Karh MK-40 nationwide (and usually do).

As a former EMT I have put together a pretty good little first aid kit (actually two, one in each vehicle), so if we get ourselves hurt, or come upon someone else injured, we can at least do some pretty good first aiding.

Our theory is that if we are in the boonies when things happen, we can live unassisted for quite a while. If in a more urban area, we can get the heck out of Dodge (if the roads will allow)...