When performing keyhole surgery, the instruments come in one of two varieties: long and straight and not very maneuverable, or extremely flexible and not very useful -- but this is about to change. Researchers at Boston University have developed something called a concentric tube robot, which uses a series of telescoping curved tubes to twist itself around the inside of the human body, while still being able to deliver enough force for medical procedures. It's been used to perform heart surgery on pigs, but it has a long way to go before it's ready to be used on human beings. You know, we weren't entirely thrilled about letting a robot draw blood -- we can't imagine a scenario where we let one of these things operate on our heart. Video after the break.