My father actually bought one of those 'Bone Fones'. I used it as a kid a few times. Believe me, it doesn't work through bone vibrations - it is just a small radio, with built in amp and a small pair of built in stereo speakers. Picture them as a 2.0 version of the Sennheiser Surrounder.
As mentioned in that link, they died a horrible death once the walkman came out.
There are a couple of them for sale on Ebay right now, Go get one Duggeh!
As for the TEAC phones, I would love to try a pair out. I obviously am not going to spend that kind of cash on them, but I am always game to try out something different.