The pictures I did take highlighted things I was interested in particular, such as side or back access into the cooking area. This seems like a great design option to me as I get tired of the brightness and heat I'm exposed to while getting in and out of my ovens.
The other oven I was particularly interested in was one made with a fresnel lens, often recovered from projection TVs. The advantage of such a solar cooker is that enormous energy is concentrated in a small space, making it possible to cook foods that need intense heat. Slow cooking is fine, but sometimes a girl just wants to do a stirfry!
The disadvantages of this kind of cooker are that it is big, it is very hot, and it can start a fire if not tilted out of the sun's direct rays. The gentleman demonstrating this oven likes to show that it can ignite a piece of 2x4 in just a couple of seconds. Obviously not for use by children or pyromaniacs.
One other oven that intrigued me was a slimline model that apparently folds down to nothing. The oven is really just the panels and then the food is cooked in a metal pot inside a tempered glass bowl with a lid. In the world of commercial solar ovens, it's relatively inexpensive and highly portable.
Of course, there are also plenty of plans online for those who wish to construct their own solar oven. Buy or make yourself one and start cooking with free energy!
PS: It was nice to finally meet NancyG, a fellow McDougaller whom I've crossed paths with online for several years. While visiting with her, who should drop by but Gabrielle, the Solar Oven Chef? You may recall her blog where she posted about cooking with her oven almost every day for a year. Now she blogs over at the Sun Oven website.