Bone conduction. No, not some heinous experiment involving a hot-plate and the contents of your Dad's underpants, it's a way of squirrelling sound into your ears by directly vibrating your skull. The key benefits are that you can still hear despite ambient noise - that means you don't have to turn the volume up - and it's far more private as eavesdroppers would have to press their faces against yours to hear it. And you'd probably notice them doing that. We've seen it before on Bluetooth headsets and mp3 players, but Pantech are perhaps the first to put it directly into a cellphone with their A1407PT.
Currently available for the Korean KDDI network, the specs are generally unremarkable - 2.4-inch QVGA display, 1.3-megapixel camera, 20MB built in with a microSD slot for expansion - aside from the bone conduction. As the vaguely confused lady in the photo above is demonstrating, you can even pretend the A1407PT is an electric shaver, while still listening to whoever it is that called you. Super discrete!
No word on whether the hump-backed handset will be available outside of Korea.
Pantech A1407PT bone conduction phone [Just Another Mobile Blog]