Firearms instructor and survivalist Colonel Jeff Cooper wrote on hardening retreats against small arms fire. In an article titled "Notes on Tactical Residential Architecture" in Issue #30 of P.S. Letter (April 1982), Cooper suggested using the "Vauban Principle", whereby projecting bastion corners would prevent miscreants from being able to approach a retreat's exterior walls in any blind spots. Corners with this simplified implementation of a Vauban Star are now called "Cooper Corners" by James Wesley Rawles, in honor of Jeff Cooper. Depending on the size of the group needing shelter, design elements of traditional European castle architecture, as well as Chinese Fujian Tulou and Mexican walled courtyard houses, have been suggested for survival retreats.
Again, the reason we tend to look sideways at those who get a little too into prepping for an apocalypse is because of their smug optimism. People actually being realistic about a dangerous future would be better served joining the military or ingratiating themselves with high-level government officials than agonizing about a little mouth scuzz or foot fuzz, right?
Your run-of-the-mill shoe stank might not pose much of a survival threat, but trench foot certainly will; baking soda is great at absorbing the moisture that might otherwise literally cause your feet to rot off your legs. As for the health of your teeth -- it will be pretty hard to get through your day's rations of homemade jerky and hardtack without some high-quality chompers. And you certainly don't want to rely on that pesky fluoride that will "kill your brain over time" (um, what?).
No one thinks they’re going to be trapped by whiteout conditions or separated from their group as night falls but it happens with alarming regularity. Don’t make things worse by being unprepared. These advanced Mylar emergency blankets cost less than 4 bucks each and weigh virtually nothing and yet can and do save lives. They’re waterproof, tear-resistant survival gear that comes in a pack of 5. As such there’s no excuse for not having them tucked away in your backpack or daypack when you set out. The very definition of essential survival gear for outdoorsmen of all stripes.
Say you're at work and a terrorist attack occurs. Roads are closed to any and all traffic but you only want to get home - even if that means walking. You may not want to grab your full on family pack in the car or you may not even be able to get to it. But you just want a light kit to get you through. How far is it to get home from wherever you may be? This get home kit should provide for 1-3 nights of traveling on foot till you make it home.