Regardless of the ethical questions involved, you've got to admit that this video is pretty cool. http://www.cnn.com/video/#/video/health/2008/01/13/mn.beating.heart.created.kare
Researchers at the Univeristy of Minnesota have taken a dead rat's heart, stripped it down to a gelatin mold and then made it beat again. They injected the mold heart with heart cells from a newborn rat and made it beat again. They are now moving on to research with pig hearts. Pig hearts are so similiar to human hearts that they can be used in a person. The scientists are also working with other organs such as, livers, pancreas, kidneys, etc. What that could mean for patients on an organ transplant list is truly amazing.