Those in society that are used to getting a paycheck every week in return for their labor may soon find their skills are not sufficient to continue putting food on the table. A true commodity is one that you can store and sell at will. It is subject to supply and demand and demand is always present for human necessities that are in limited supply.
Labor can be a commodity of sorts but it cannot be stored for later sale, trade or use. Everyone is limited to the same 24 hour day and time is the great equalizer in that regard. Unskilled labor in and of itself is in large supply so you will be subject to the same supply and demand fundamentals as everyone else. This is the reason you should not rely on your physical labor alone as a trade-able item in a collapse scenario. The more unemployment there is, the less your labor will be worth.
The one source of labor that can be in demand at any time is knowledge. The knowledge you posses is more trade-able in a crisis than your physical labor will be. Anyone can lift the hood on a car but how many can diagnose and fix a malfunction when it stops. How many have the knowledge to identify and bypass the problem if needed parts are not available? Knowing what wild plants are edible, have medicinal properties or can kill has a value. Knowing how to produce a liquid fuel alternative or create electricity from a pile of junk parts has a value when energy is lost for long periods. Knowing how and where to find food and store it for long periods has a value. Construction knowledge or advanced lifesaving procedures may not be in demand every day but when they are they cannot be replaced easily. The larger your base of knowledge is the more trade-able barter currency you will have.
The ability to raise a product to sell or trade is the power to control your life. This may be nothing more than growing some vegetables. The ability to produce something from little or nothing is a skill that many do not posses and will produce a commodity that others will be willing to trade for. Money really does grow on plants when you can take a few dollars worth of seed and produce hundreds of dollars worth of products. It’s better than having a printing press. The ability to produce seed for sale can command a high premium when supply is low and demand is high. The ability to produce livestock products is a step higher in the growing of commodities but the higher price will also reflect more hazard and labor.
The grow ability can also include the production of natural resources that are limited but available to you. The harvesting of trees or tree products like maple syrup, fruits or nuts should not be overlooked. The recovery of natural minerals such as salt, iron ore, coal or even precious metals bring commodities into being that did not exist before and may command a premium in society.
The ability to take a raw material and make something useful from it that society needs is another way to produce a commodity for sale or trade. Knowing how to make cooking oil, alcohol or bio-diesel from crops and having the equipment to do it will provide you with a commodity to sell or trade. Having the knowledge and equipment to make textiles from crops, reprocess scrap metal into tools, process animals for food, build furniture or boats or repair broken items will provide you with a usable commodity when you need to barter. The make function is a combination of knowledge, materials and tools that can also be used as a function of labor to repair items for others.
This can also extend into the realm of transportation and communication as well. These items will require the means to repair and maintain the function and will almost certainly require the production of materials and energy for their use by you. The ability to transport people or products by truck or boat or provide vital communications over long distances may be a commodity you can provide to others. The make function goes beyond the typical labor function and provides a useful service or product that is in short supply.
The worse the supply situation is in society and the more you know, grow or make, the better your chances are of getting the things you need and use. A self sufficient mentality will provide you with many of the skills and tools you will need to provide these three things in society. When fiat money fails, what you know, grow or make becomes the new barter currency until stabilization brings forth a new medium of exchange. Having a supply of barter goods is great but over a long period you will eventually run out. That is why know, grow and make will be necessary for long term situations. The basis of all commodities is knowledge so that is a logical starting point if you feel the need to insure your value in the future no matter what happens.