OregonMouse, I initially thought about some kind of home brewed mix like what you listed, but those little packs sure are handy and light, they include the salt and potassium, and I really don't need the glucose. Of course, I'm trying to just maintain hydration, as opposed to rehydrating after getting dried out.

My first thought was the old salt pills like they gave us in the military, washed down with plain water...but I find the electrolyte water with the salt and fruit flavor easier to get down and keep down than plain water.

On a related note, I was watching a Dual Survival episode last night, about the guys surviving high in the Peruvian Desert. Cody Lundin got freaked out early on, and they had an awesome shot of him puking up all of the precious water he just drank. So, keeping it down once I drink it is always a consideration.