My wife has tried to dehydrate probably everything. With usually pretty good results. However a word of caution: Do Not, and I do mean, Do Not dehydrate meatballs for your spaghetti! You could put them in water today to start rehydrating with the plan to eat them for Christmas dinner in 2012 and still have some one injured! We've never laughed so hard in our lives until we tried to have spaghetti and meatballs for dinner one night in Grand Gulch. You get camp set up, make a couple cups of tea while your dinner is rehydrating, feeling tired, content, and very hungry. However you're better off setting the meatballs to the side. Don't throw them, you may put someones eye out. We brought some back with us and tried to rehydrate them at home, I won't live long enough. However I did choke down three that night. I told you I was really hungry!
Honestly though, my wife makes a cookie/granola bar that I call her "survival biscuit" that has a lot of nuts, grains, whole wheat, flax meal, and God knows what else, that you could survive on. I usually have one of those for lunch when we're hiking.