Micro CT provides high resolution 3D images useful in biology and surgery. Micro CT provides the basis for a new, multi-institutional project for sharing and viewing such images, the “Virtual Museum of Natural History”™, which now has 1200 stacks of ~900 specimens, including 722 mollusk shells of 198 species in 172 genera, animal eyes, marine eyes, de-identified human autopsy specimens, brittle worms, annelids, cephalopods, various vertebrates, and seaweeds, many of which can viewed on: youtube.com/channel/UCGCBXNkhm6BMQxtV_Thvkmw. Micro CT’s use in medicine is exemplified by the absence of rapid, detailed, 3D, information on surgical specimens, which has long been a major barrier to success in many aspects of surgery, especially in cancer surgery. For example, at the present time, approximately 1 in-3 breast cancer patients go home with cancer in them, and not discovered until a week later, when the pathology slides are examined, and, for a small number of patients, cancer remains at the surgical site, which is not known until many months or even years later when a local recurrence occurs, This results in return for further surgery, and approximately 2,000 deaths/year, which might be prevented by detection at the time of the initial surgery. We have demonstrated that Micro CT can provide useful 3D images for many surgical specimens, including identifying margin positive breast cancer patients in 10 minutes, and locating lymph nodes. This work has shown that Micro CT can provide rapid, accurate, actionable information on the surgical specimen while the patient is still in the OR.