Is it possible for my HTC phone to interupt my music when I receive a call? I frequently miss incoming telephone calls because I am listening to my iPod Touch.

Does anyone know if it's possible for my iPod to detect incoming calls on my mobile phone (an HTC Desire) and alert me to the phone call?

I've seen bluetooth connection devices that purport to do this (such as the GEAR4 BluEye), but they are several years old now.  

However given that this kind of hardware exists, and that the iPod Touch has Bluetooth built-in, I wondered if there was an app or setting that would enable the phone and iPod to work together in this way?
I'm pretty sure, you can't do that. You have a bluetooth connection between your iPod and your headset - your mobile phone cannot close this connection or notify you over your headset. So you may have to buy an iPhone or use the HTC to listen to music... :)