Seriously, though. A friend whose daughter has synethesia pointed me to a Facebook group about it, and I discovered many types I didn’t know existed, including some personal quirks that I had no idea were related.
One example: If I massage someone’s shoulders, hands, or feet, I can tell what it will feel like because I can sense exactly where on MY body it would be. Apparently that’s not normal.
And neither is mentally seeing the week or a year (like a calendar) in your head with a specific shape and with colors. For me, a year has three rows with 4 months in each, and each month is a color.
I know synethesia tends to run in families, so I a few years ago, I asked my older sister about it, and she has it too — but we’d never discussed it. I was about 40 at that point.
A cool historical figure who had it: composer Jean Sibelius of Finland, for whom major keys had color. (Not minor keys, go figure.) He had a big fireplace tiled in granny-apple green that he called F major, and a painting in the house that had a lot of a specific yellow he saw as another key (G major, maybe? I forget.)
The same friend who shared the FB group with me also told me about an Oliver Sacks book that discusses it, Musicophelia, I believe, and she’s quoted in it. The book’s still in my enormous to-read pile, but I’m excited to get to it.