Free: Contests & Raffles.
(although I was very happy with my "kitchen"- did the freezer bag cooking thing and will never look back to mountain house- guts were happier too).
Whuppinstick, check out http://www.trailcooking.com/ for a start. I've kept it to simple, one bag meals, about 4oz each. You will see there are all sorts of elaborate things to try and do- their is a cookbook published by the gal behind that website. You'll need a dehydrator. I enjoy putting everything together, tailored to my tastes. You get to pick your portion size etc., lots of benefits, the key drawback may be that it is time consuming to prep everything.