While I don't talk about it much on this website, I'm a real-life practicing doctor. My specialty is Pathology and Laboratory Medicine, so I enjoy seeing displays in museums that cater to my area of interest.
The Museum of the Rockies in Bozeman had an interesting display on Paleohistology -- the microscopic study of fossilized tissue. I'd heard of Paleohistology being done on human mummies and bugs trapped in amber, but this was a new one for me. The image above describes some of the technical details. Obviously fine detail is not available, but the sections allow a low power study of bone architecture, from which a lot can be learned.
Perhaps something I need to pursue when I retire.