There are a number of clinics worldwide that are offering unapproved stem cell therapies, including the examples cited by the previous poster. While stem cells are considered to have a lot of potential uses, the only stem cell therapy currently approved by the Food and Drug Administration for routine medical use is bone marrow transplant for leukemia and sickle-cell anemia patients.
Additionally, there are a number of different stem cell therapies in various stages of clinical trial, all of which have shown some promise. These include potential treatments for Lou Gehrig's disease, various ischemias of major blood vessels, spinal cord injuries, macular degeneration of the retina, and many other conditions. You can see a current list of clinical trials involving stem cell therapy here.