http://www.msnbc.com/news/786016.asp
to quote:
“Are you ready?” he asks, then points his invention
directly at the head of someone who’s just entered
the room 10 feet away. “Now, can you hear it? Can
you hear it? Isn’t that unbelievable?” What the
person across the room hears is, well, unbelievable:
all of a sudden, the sound of a waterfall has
materialized in his head. "
...
"The Hyper-Sonic Sound System (HSS), as he calls it,
can take an audio signal from virtually any source—home
stereo, TV, computer, microphone, etc.—and convert
it to an ultrasonic frequency that can be directed
like a beam of light toward a target up to 100 yards away"