Solar Cooking
Using the sun as an energy source for cooking is not only resourceful, but a lot of fun! The following website provides some great information about solar cooking.
One of my favorites, because of how easy and cheap it is to make, is the BYU Funnel Cooker, http://solarcooking.org/plans/funnel.htm If you've seen a car-sunshade cooker, it's the same concept. Dr. Jones' goal was to come up with a well-functioning cooker that would be easy for anybody to make with whatever materials were available.