Cancer biopsies are scary. The patient gets tissue removed from his or her body, the sample gets sent off to the lab and then there's the agonizing wait for the results.  Dr. Stephen Boppart of the University of Illinois Urbana-Champaign, both a physician and an engineer, is working on instant biopsies that will produce results in minutes. Using laser light and artificial intelligence, Dr. Boppart and his colleagues have been able to identify cancers early and accurately. Moreover, this technique promises to identify conditions in the body that might lead to future cancers by looking at tiny vesicles, liquid-filled sacs that act as messengers.  His "Town Talk" sponsored by Telluride Science, was recorded at the Telluride Mountain Village Conference Center in Colorado.  The program was moderated by veteran broadcast journalists Judy Muller and George Lewis.