Reading every reply leaves me asking why everyone is so concerned with necessity? You can start at a GPS, go through everyone's specific item or list of items and none of them are wrong, even the GPS. A GPS has got to be near the top of most life saving and convenient toys ever made by mankind, and they just keep getting better. Can you survive without one? Most of the time. Just like you only need a dentist once in a while, but when you do... I agree that you can't take it all. I continue to try to all the time, but you sure as hell don't have to scratch a GPS off a list because of anyone's idea of what a necessity is or isn't. Make a list of everything you can think of that you might want to have while Touring. From a tire patch to a Rum and Coke on ice. From a lifesaving zip tie to portable pressurized shower. Good food and everything necessary to make it. Not just an Altoids can 1st aid kit but one that could save a life in the right hands. Creature comforts to life-saving fire starters. Once you have the list and have actually researched the products to fully understand their function, cost, practicality, durability and weight, then start to prioritize them. Use whatever factors are most important to you, i.e., cost, weight, necessity, cool factor. If you don't have the money for something then you aren't going to buy it, yet, but that doesn't mean it has to come off your list. I have a Rohloff SpeedHub and love it, but it's $1600.00, If you can't afford one now you may in the future. I ride super heavy and pull a trailer. It's not my favorite but I can get most anywhere I want to set up camp and do day rides out of. Anyone of you would load a car and drive somewhere to ride trails for a week. Some... people will fly a bike to the top of a hill to coast back down, future generations be damned. Why stop and sleep in the dirt or ride all day in the rain with no overshoe to keep dry? The more you have with you, the long you can go, the more comfortable you can be, and the more fun you can have. Take all you can (within reason and common sense) and enjoy every bit of it. When you determine the maximum weight you can move getting to base camps you can start working the list to determine necessities for where ever you are going. Do I need snowshoes riding down the gulf coast? If I do something is terribly wrong. Do I need a stainless steel hand operated nose hair trimmer ever couple weeks, yes, yes I do. It's a necessity. Does it have to be electric, not at all. Also, think of it this way. Is insulin a necessity to a non-diabetic? Make your own list through experimentation and experience. What about condoms, hummmmm, but they are really light, it's Always a good idea to have a few, just in case.