I know the subject has come up before about synesthesia here, but has anyone ever heard of someone being able to taste music? I've been looking around the interwebs to see, because this happens to me, but my google fu is weak.
Most of what I've heard is anecdotal. I know of people who see colors depending on the sounds they hear.
I've also heard that grapes smell further away than apples (Only rumors).
Also, also, I have an ASMR type of sensation that I was able to gain control of with experimentation. As far as I know, ASMR is a similar, but more simple kind of synesthesia. As in, neurologically unrelated, but semantically functions as a subtype of synesthesia. I could be wrong about that.
/self-centered tangential rant
Anyways, from what I've read, pretty much every combination of synesthesia you can think of has been found. I believe Hack-A-Day had an article on a device that would simulate some form of synesthesia, and their method was interesting. But for the most part, I don't think much testing or study has been done on the subject in terms of academic journals and whatnot.
ASMR is really interesting. Most people have experienced it, as far as I can tell, but only some experience it regularly with a controllable stimulus. It's not, as far as I can tell, related to synesthesia at all, but it also hasn't really been studied at this point.