metatron....It's more like, "That kind of music sounds like an orb spinning to the left while flat disks bounce from the bottom, all in a mist of orange and green." Seriously.
My syn is sound -> color/shape/texture, emotion -> color, shape -> color/temperature/personality (the last one only involves the shapes of letters and numbers). On rare occasions I've experienced a reversed color/emotion -> shape. Of these, the letter/number -> color type is the most common. My experiences also range the gamut of associated syn (i.e. one sense evoking another sense) and projective syn (i.e. one sense stimulating actual perception in another). When my syn is projected, I literally see the sounds and colors and shapes quite vividly. But it is fairly rare when it gets really vivid.
I suspect it is not that uncommon...I keep meeting others with it all the time. There are also probably synesthetes out there who have it without really realizing what it is. For instance, I believe people who see auras are probably experiencing projective emotion/temperment/personality -> color synesthesia. Anyway, it is a huge boost to my enjoyment of reading and music...wouldn't want it any other way.
Here is my name the way I see it:
I added motion blur because the letters do blur together like that when they occur within a word. Also, my favorite color is green and it is no coincidence that my name here is dominated by green color. I gravitate toward aesthetically attractive words, names, etc. that emphasize the colors and color combinations I like.