Not to get too off into this tangent, but there *is* 3-D sound, though it
has mostly been used for radio dramas and other all-sound productions.

The foremost piece of tech used for this is the (and I *hope* I'm
spelling this right) Kuntskopf Binaural Sound System...essentailly a plastic
"head" with speakers in either ear, which is literally taken to locations in
question and the actors or actions move around it, with the result that when
you put on headphones, you can hear the sound moving on either side, in front,
and *behind* you, passing clearly in a circle.

It can actually be a fairly unnerving experience the first time you
experience it. If you contact ZBS Media out on the East Coast, you *might*
still be able to get their production of Stephen King's THE MIST, which used
this technology.

jms