I attended a conference last month on rare neuroimmunological disorders. There were several presenters there from Johns Hopkins who are doing amazing research with stem cells. They have been able to transplant stem cells into a paralyzed rat an it is able to walk again.
There is some information on it here: http://www.hopkinsneuro.org/tm/
I have not participated in a study yet, but I am planning to have my medical info put into a database called "the Accelerated Cure Project."
It is primarily researching MS, but my condition (transverse myelitis) is somewhat similar and is being included in the research.
I'm really excited about the research being done, and plan to be very politically active about getting the current ridiculous restrictions lifted as soon as the 2008 election is over.