What's better than putting a microphone right next to your mouth? Turning your whole head into a microphone! That's the goal behind bone-conduction technology, which uses the vibrations of your skull to determine what you're saying. Because it relies on vibrations instead of sound waves, bone-conduction technology has the advantage of isolating your voice from all the background noise (though, one has to imagine that if you were standing right next to a speaker thumping bass, you might still run into some interference).
Danish company Nextlink is marketing a wireless cellphone earpiece based on this technology, the Invisio Q7. It'll be available exclusively at Radio Shack, for $200, by the end of the year. For those of you wondering how the hell that thing fits in your ear, I have no clue.