Man, I just read a children's book about a girl who had this and I thought it sounded totally beautiful. You might want to check the book out- it's called "A Mango-Shaped Space". It claims acupuncture looks pretty wild!
I do the same with smells and shapes. It usually happens with perfumes or colognes. Some people think its weird but I think its rather fun.
I had no idea other people experienced this, or that this phenomena actually had a name. Thank you so much for posting this.
http://www.mindhacks.com/blog/2005/08/pilot_magazine_for_s.html
pilot magazine for synaesthetes. (student project). good stuff.
This is obviously a very old entry, but I wanted to start from the beginning on your site and this was the third entry I read. I, too, have synesthesia, and it's great to find someone else out there who has it. Obviously, everyone's synesthesia differs, and mine is not entirely like yours, but has some similarities. I see 'personalities' in colors, fonts/letters, shapes. I assign color to sounds, and I see shapes when hearing music, as well as colors. I have perfect pitch. If you ever want to talk to someone else who has it, I am here. I've always wanted to. I only found out it had a name about 3 years ago when I found an article about it... anyway, be well :)