Sanyo Electric's TS-41 cell phone is unique: It has a transducer that creates
sound directly through vibrations in the bones of the user's skull, thereby
making it easier to hear in noisy situations. 

As first glance, there's nothing special about the TS-41 cellular telephone.
The phone, produced by Sanyo for Japan's Tu-Ka Cellular, seems similar to
most others on the market. The clamshell handset has a 2.1-inch main display
and a smaller display on the outside of the case. It can be used for talking,
wirelessly browsing the Internet, and sending and receiving e-mail. 

What's special about this phone is what Tu-Ka Cellular calls the "sonic
speaker." It's located inside the top half of the case towards the hinge and
works by producing vibrations that travel along the user's facial bones to
the ear. The advantage is that you can easily hear what people are saying in
loud environments, according to the manufacturer. The phone is on sale now
with an operator subsidy for around $90. It's compatible with Japan's PDC
phone system only and won't work elsewhere.