Ok, I'll confess to having two unusual daughters.
My oldest is a synesthete, she sees letters as colors.
My youngest has a couple of "gifts". When she sees something that is written, she will automatically group all of the letters by odd and even. I first realized this one day as we were driving. She was saying "odd' "even" to herself. I asked her what she was doing. She pointed to a street sign that said "Lake Elmhurst St Exit", she said "odd". Then she pointed at the next sign "Heron Boulevard Exit", she said "even". I asked her what she was talking about. She can glance at a word or even a long sentence and
instantly tell you if the number of letters (including spaces) totals an odd or even number. She can also do this as a person is speaking. She can also regroup all of the letters instantly into an even number for the total by adding or subtracting letters from words. Hearing her do this is bizarre as she goes through all of the letters, rapidly regrouping them and looping the sentences. This is hard to explain. She can also look at any object and
instantly tell you how many distinct geometric shapes are in it. It takes her only a fraction of a second to do this. She can do this with entire walls with bookshelves and pictures, etc...

She's also one of those people that can make multiple folds in their tongue.