Going to the doctor can be expensive, especially for those that are under-insured or flat-out uninsured. Unfortunately, many who fall into those groups simply avoid going to the doctor all together, which may save money in the long run but could be extremely dangerous for their health. But one doctor has been trading free and nearly free office visits for smiles. Dr. Michael Zollicoffer is a family practitioner in Baltimore, Maryland and for the past 40 years, he's been running his medical practice on a "pay what you can" policy.