gun or other nonliving things, but the next thing is replacing organs? printing organs? >> exactly. it's amazing technology. it uses the same technology as an ink-jet printer. we have a matrix of skin cells and organic compounds and the computer generates this three dimensional image that's a living organ. this could solve so many problems in medicine with organ shortages for heart transplants and kidney transplants and the like this. has been accomplished already with children born without a windpipe and three dimensional tracheas that are implanted in the children and doing well now. we'll be able to serve patients who normally may die waiting on a transplant list. john: which is about 18 people a day, most waiting for kidneys. >> exactly right. john: and wake forest, where