I will tell you a little story about Nelson, our hackerspace member here in Shanghai. Xinchejian, the Shanghai hackerspace is quite a breeding station for new engineers. Nelson did prototype a new kind of headphones which enables you to share your music with many others via Bluetooth and an App. Control play/pause, volume, next song etc. via a touch sensitive surface on the right earcup. But I will shut up now. Go and see on Kickstarter: Wearhouse Arc- Wireless headphones reinvented
