Wow, since I’m a heart patient, I like this new one from NewScientist.com:
A device that sounds like a 21st-century version of a medicinal leech may soon be set loose inside the chests of heart patients. Resembling a robotic caterpillar, it will crawl across the surface of their beating heart, delivering treatment without the need for major surgery.
Physicians used leeches from the ancient Egyptians to the early 20th century. It was a nasty process which usually killed the patient more than it cured. Fascinating read.