There's more than a little 'gee whiz' to the idea of hooking up a small device to your earbuds that would turn them from passive music players to smart sensors. After all, there are hundreds of millions of earbuds out there, and they could all be easily converted in this way. But there's the other side of this: now we have to be careful about buying earbuds that will spy on us. The chip might be built into the phone or it might be build into the earbuds. Either way, whether we benefit or not, we're unwittingly sharing yet more personal information.