EurekAlert reports on a small step forward in the search for alternative sources of stem cells. A number of different groups are working on ways to make cells in the body reverse their differention to become stem cells or some other form of progenitor cells. The regenerative abilities of some lizards seems to depend on this or a similar process, for example, but scientists are still working their way towards establishing a basic understanding in this area. We just don't know what is possible in humans, and thus embryonic stem cell research is still vitally important to progress. You can read up on stem cells at InfoAging, a very good resource for this sort of information.