You know that neat trick salamanders do, where if you cut off one of their legs they can just grow it back? Scienticians are working on making things work like that for humans.
Turns out the human body is actually wired in some ways to heal like that, and strides have been made in stem cell research to have people actually grow back lost fingers.
SciAM has a great — if lengthy — article on the science behind such advances. If you’re into medical science, or think the idea of regrowing limbs is neat, it’s a good lunch-time read.