This may sound like something out of The Hitchhiker’s Guide to the Galaxy, but it’s closer to regeneration a la Dr. Who. Or rather, it’s the first step toward that staple of SF, cloned body parts to replace ailing originals. And better in this case, because you don’t have to grow a whole clone, with all the ethical questions involved.

It’s widely agreed that two heads are better than one, so when can I put in my order? 😉