I have three arms and two heads.
More seriously, I have more blood vessels in my retina than I'm supposed to have and my vision seems to improve as I get older, which makes little sense. I haven't taken a formal eye test in over a decade but a rough-and-ready read of a test chart suggested my vision is somewhere around 20/15. I have a friend who is an optometrist and who was surprised by that so he handed me a chart to test my reading vision, and I could read the smallest letters without hesitation.