Researchers at Houston's MD Anderson Cancer Center have announced that they have successfully used an engineered "smart virus" made from the common cold to destroy brain tumors in laboratory rats (which I've always thought were pre-disposed to cancer...).

An article from Wired provides some cautionary comments from throughout the health industry, including the American Cancer Society", but the research looks promising.

The biggest issues seem to center around the use of viruses that we may not understand how to control, but then again, we're humans, we like opening Pandora's Box.