Granted, all humans are around 99.9% genetically identical. Most of us have a few limbs, a face and plenty of shared behaviours and customs, but in that little 0.1% there are plenty of little quirks, oddities and differences too, some of which are super rare.
You might have lived your whole life with a weird feature or ability that you thought everyone had. Some of these are as mundane as being left handed - something only 10% of the population share - but plenty of rare quirks are much weirder and more wonderful than that.
Some are evolutionary throwbacks, some are peculiarities of our big, complex brains and some are just straight up superpowers.
If you have any of these, you could genuinely be one in a million (although you knew that already, right?). Most or just cool party tricks to mildly entertain your friends, but there are some that could indicate something interesting, or even worrying, about your genetic makeup.
One harmless mutation, for example, offers us a glimpse into your evolutionary past, but something as innocent as tickling, could well land you in a psychiatrist's office.