Bluetooth headset
The GN Netcom 6100 is the only Bluetooth headset that works with both cordless and cell protocols. There are many others that work only with cell phones. Since cell-only connections are impractical to deliver the Consumerium buying signal (they cost money which may exceed the price premium, only such dual-mode headsets could actually deliver audio over Bluetooth for a Consumerium buying signal in a friendly retail location. However, the inherent limits of Bluetooth make this unlikely to work except in very small stores:
Since it works only 10 metres away from its own unique no-handover base station, it's not very useful even as a replacement for a cordless. Because of the limitations of Bluetooth it probably can't act as a full function audio device except when it is replacing some cubicle-like or small-apartment corded phone system. For those few people who stay within 10 metres of some station and really hate just putting another headset in their pocket as they shift to the cell headset, this might be useful.