[ChuckMcM]

I have wondered about this as well. Certainly the combination of an in-ear device and some external sensors would be killer at parties. Look at someone and tap your ear, they get a ping that you'd like to chat with them and you enable a conversation.

For the UX folks it would be interesting to design a chat UI where the inputs might be things like head tilt, nods, shakes, taps, and voice.

The smarts don't have to be in the hearing aid either. My phone and my tablet can be the 'processing' power with the WiFi/4G connection.

[ktizo]

I've been thinking about this very thing.

Accellerometers and gyros in the headphones linked up to Openal for a 3d computer interface that doesn't require sight.