In the last decade, we have all received periodic exhortations to be prepared for the next major man-made or natural catastrophe by putting together a “disaster kit”. These all are some variant on the same theme, generally some mix of flashlights, first-aid kits, radios, batteries, food and water for three days, and various other bits and bobs (apparently now not including duct tape). A good example of this is the government-blessed kit described at ready.gov. Further, nonprofits and companies have seized the opportunity to make some money out of this with a variety of bizarre objects specifically designed for your kit (if you don’t believe me, check out some of the available gadgets at the Red Cross store). Having this kit, together with a family evacuation plan, is supposed to prepare us for the next major catastrophe.
There are three problems with this. First, a kit is only as useful as your knowledge of what to do with its contents, and it’s workability (food not expired, batteries not leaking, etc). You do not become an expert in emergency medicine by buying a first-aid kit; rather you become an expert in emergency medicine through training and experience, and then assemble the equipment you need based on your training and experience. Second, the kind of kits described are almost laughably inadequate for many real emergency situations, in the same way as cowering under a table is not likely to protect you from a nuclear detonation. Third, by definition a “disaster kit” is something you will probably never use, versus something you get used to using day in and day out. Thus I think it’s better to think in terms of everyday items that will help in a disaster, rather than a designated “disaster kit” (for example, I think it’s best to keep a “rolling buffer” of 2-3 weeks’ worth of food - that is, you just keep extra stock of the stuff you use normally - than having a separate “emergency food supply”).
So my suggested strategy is to start by figuring out what kinds of disasters you need to prepare for. This is not a trivial task, and some disasters will always take you by surprise (think the Blackout of 2003 for instance). However there are well established ways of prioritizing potential hazards based on probability, impact, and mitigation. Emergency managers are trained to perform hazard risk analysis with the “all hazards” model, and most communities maintain a list of the top hazards in your community. Try asking your local emergency manager for a copy of this as a starting point, or try to create one of your own for your household from scratch (you can even take an online FEMA course to help you do this). A simple way to start is by making a list of all the things you think could go wrong, and for each designate a percentage probability it will happen in the next 10 years and write a sentence or two for each on the potential impact if it did happen, and what you have already to mitigate this impact (for instance, having a generator and fuel can mitigate the impact of a short power outage). You can then manually rank them based on these factors.
Once you have gone through this exercise, start preparing for the ones near the top of your list. Think about what you would need to do in each circumstance, and whether there are plans you can make or things you can do, to mitigate the impact. For instance, keeping your gas tank in your car half full mitigates a variety of disasters as it enables you to evacuate up to 200 miles or so (depending on your fuel tank size and mpg) to escape a regional (but not widespread) disaster. These mitigation steps naturally lead you to equipment that you might want to have on hand for a disaster. As an example, take a look at my list of ranked hazards and mitigation steps.
You can also do some training that will help you in an emergency. Practice living without power for a couple of days, in both summer and winter. Train as an EMT or First Responder to give you skills you need if you can’t get medical help in a disaster. Buy a tent and go camping -- this gives you the flexibility of living pretty much anywhere. Think about strategies for keeping warm in winter, and cool in summer. Make sure you know how to turn off your water and gas. In this way, you learn new skills, have fun in the process, and you’ll be much better prepared for the next disaster when it strikes.