I have numeric/spatial synesthesia! I used to assume everyone else did, too. Every number is assigned a different place on a giant, invisible roller coaster (which may explain why math was so confusing to me as a child).
That's just to thirties in 2 dimensions, but there are hills in there, too. (shucks, it left aligned the whole thing.) That's just for counting. It's different if we're talking numbers as related to people's age. I see the months of the year this way, too.
Also, I strongly associate certain pitches on certain instruments with touch.
I think it's an incredibly fascinating thing. I've figured out that I have 7 forms of it:
(In order of strongest to weakest)
Music - Color (it's like fantasia!)
Personification - Color (everyone has a specific color)
Emotion - Color
Touch - Color
Music Notes - Color
Pain - Color
Sight - Touch (example: looking at a TV... I can feel the TV in its shape, weight, static, etc. But this happens very rarely)
Everyone in my family has various forms of it, but they're not all the same as mine, and vice versa. My Dad has various numerical forms and my Mom and Brother have Grapheme versions.
Anyhow, I think it's incredibly fascinating. Share!
I imagine how music is played when listening to it. And I connect a specific colour to everything that is important to me.