I.N.C.H. pack: I'm Never Coming Home pack. (It is another name for a Bug Out Bag. often used by those trying to show that they are experts in the preparedness field.) A pack containing everything needed to walk out into the woods and never return to society. It is a heavy pack loaded with the gear needed to accomplish any wilderness task, from building shelter to gaining food, designed to allow someone to survive indefinitely in the woods. This requires skills as well as proper selection of equipment, as one can only carry so much. For example, instead of carrying food, one carries seeds, steel traps, a longbow, reel spinners and other fishing gear.
The increased inflation rate in the 1960s, the US monetary devaluation, the continued concern over a possible nuclear exchange between the US and the Soviet Union, and perceived increasing vulnerability of urban centers to supply shortages and other systems failures caused a number of primarily conservative and libertarian thinkers to promote individual preparations. Harry Browne began offering seminars on how to survive a monetary collapse in 1967, with Don Stephens (an architect) providing input on how to build and equip a remote survival retreat. He gave a copy of his original Retreater's Bibliography to each seminar participant.
For global catastrophic risks the costs of food storage become impractical for most of the population  and for some such catastrophes conventional agriculture would not function due to the loss of a large fraction of sunlight (e.g. during nuclear winter or a supervolcano). In such situations, alternative food is necessary, which is converting natural gas and wood fiber to human edible food.
To me, the best option is to store emergency food. How much? If you have none, store enough for a few days. If you have enough for a few days, get enough for a week. How much you store depends on what time frame you think you're at risk for having to be completely independent. The early settlers of the southwest liked to store enough food for a whole year and still do to this day!