I had the good fortune of being able to view the Leonardo da Vinci exhibit at the Seattle Museum of Flight when it came to town. It was quite well done with pictures and models of his designs, reproductions of his most famous paintings, computer simulations of the kinetics of his mechanisms and even an actual page of the Codex Leicester (da Vinci's most famous journal). I can't read Italian, especially backwards, but it was neat to see something that he had written almost five hundred years ago still intact (there was a blown up copy with an English translation next to it). I was a little disappointed though that there was not more on his bridge and dome designs.
The Roelofs web site that I provided a link for goes into quite a bit of detail on da Vinci's bar grid designs and their use in dome construction. It also shows how this structure can be adapted for spheres and other geometric constructions. This image is essentially an adaptation of this structure. One difference is that I am using flat components that are bent under stress instead of starting with curved components. I also chose a pattern based on geometry that is different from the ones covered on the Roelofs site.
The quote in the background, unreadable at this resolution says: "Men of genius sometimes accomplish most when they work the least, for they are thinking out inventions and forming in their minds the perfect idea that they subsequently express with their hands." - I need to use that excuse more.