freeryan.com

Yesterday the Department of Defense announced the creation of the Armed Forces Institute of Regenerative Medicine. This means they have a department specifically devoted to growing new human tissue.

If you read Scientific American, or are tuned in to the wild world of modern science to any degree, you'll already know that thanks to the wonders of stem cell research and other techniques, scientists are able to grow living tissue. But not just tissue, actual organs: "...blood vessels, livers, bladders, breast implants... [and] beating, disembodied rat hearts" (source).

Here's a fairly comprehensive article on the whole thing: http://www.sciam.com/article.cfm?id=regrowing-human-limbs