I love the work that Larry Witmer and his students do at Ohio University. Not only is it cutting-edge anatomical research that helps us better understand prehistoric organisms, but the Witmer lab is constantly sharing parts of their work via the web. They even have their own YouTube feed with lots of 3D renderings of fossil animals, including one of my favorite prehistoric mammals, Archaeotherium. The video below presents a view of its skull and brain cast, as well as a quick look at its jaws in action: