I work in construction and it is HOT in the summer in Arizona. Drinking water day after day can get boring and I eventually go to Gatorade or Dr. Pepper to change it up. In tough times, those things may be more difficult to come by, but just as desirable or more so. If you have to boil or filter water, sometimes you may want to hide an unpleasant taste. Powdered drink mixes are a long term storage solution.
I like Gatorade powder personally because it tastes just like what you buy in the bottle and I have always drunk it. It is sold in cylindrical cartons, bags, and even individual packets for mixing in a 16oz bottle. Tang is another oldie that comes in bulk quantities to store long term. The LDS church offers a berry fruit drink mix which costs about $3 and contains many vitamins and nutrients. I believe natural fruits and veggies are the best way to take your vitamins, but if you don't have a garden, the powder drink will have to do. They don't seem to sell it online, but you can find a local storehouse online.
There are about a thousand choices in your local grocery store so store what you like.
Pictured above is their hot cocoa mix which is one of my kids favorites. Nestle hot cocoa is also a good one that you can buy in a can and store (if it lasts that long).
Milk is another source of vitamins and minerals and is used to cook a large variety of things. If you don't own a goat or dairy cow, you are out of luck. Canned milk is available in your local store and will last a year or two. Ultrapasteurized milk in the 32 oz. boxes will last a year or two as well. The LDS church stores powdered milk in foil bags to prevent moisture and light from penetrating the bag and claims on the bag that it will store for 10 years if kept in the right conditions. It costs $5-6 dollars a bag and I have many bags of the stuff. Great for cooking and drinking.
If you find that you can't live without coffee or tea, there are powdered versions of those thing as well. Don't forget to have it stored away. You can store K cups if you have the money to spend and like those things. Remember to always store what you like if you can. It is a comfort in tough times. Later!