I can't just draw surfaces. I have to understand what's going on inside a subject, how everything fits together -- this is why those zen psychobabble "release your inner artist" and "draw what you see" books aren't much use to me. It's also why the tendency of furry artists to draw tails coming out of the middle of the back not only annoys me, it actively makes me queasy.
In costuming, my designs for my dragon mask have been based on the idea of building a lightweight, open, sturdy frame that mimics the lightweight, open, sturdy skull construction of the dinosaurs. Working from 2D technical drawings and even photographs has its limitations, though, especially with something as complex as a dinosaur skull.
The Digital Morphology Lab at the University of Texas solves that little problem. They've digitized skull and skeleton models of all manner of biological specimens. You can do full rotations in all three planes. It's gorgeous, and gives a really good feel for complex structures.
The Tuatara was the first page I found. It's a very complex, intricate diapsid reptile skull, and really shows off the technology well. You can really see how all those struts and arches fit together.
Hope folks find this as useful as I will, in both costuming and drawing.
And, heck, it's just plain cool.