James Harrison has magical blood.
Specifically, his blood contains an extremely rare enzyme that can be used to treat babies dying of Rhesus disease. If you've never heard of that disease and figure it's not a big deal, well, wait for the numbers.
Harrison, being a generous type, has donated his rare, life-saving blood roughly 1,000 times over 56 years. This has saved the lives of--seriously, you're not going to believe this--over two million babies around the world.
"Yeah, two million. I'm hoping to hit three, but whatever. I'm in it for the babies."
The whole thing is kind of a "pay it forward" situation for Harrison, who needed major chest surgery when he was 13-years old, and soaked up 13 liters of blood over the course of three months. "The blood I received saved my life so I made a pledge to give blood when I was 18." This has turned out to be the second most important vow in history.
Not only is he continuing to save lives every day now that he's entering his twilight years, but his blood has also been used to develop a vaccine called Anti-D to keep those babies safe. Forever.