Since it first appeared in America in 1985, there has been an intensive amount of interest in a treatment of some sort of the Auto ImmunoDeficiency Syndrome, or AIDS. Other countries may have been interested when first exposed as well. And according to Slashdot, we may now have it. Supposedly, 3 people have been completely cured of the disease, which was previously minimally treatable and guaranteed fatal.
This is still tentative and prone to additional testing, since case #1 apparently has some radical differences with cases #2 and 3, covered in the article. The theory relies upon bone-marrow transfer immunity. When you receive a bone-marrow transplant, you inherit with it the donors immune system capabilities, including all vaccinations. In this case, one of the rare people who was completely immune to AIDS (for genetic reasons mostly) donated bone marrow to these two patients, who inherited the immunity.
If this can be confirmed, this will mean a radical new hope for the world's suffering. Still no cure for the common cold or herpes, though.