Bluetooth headset for two phones

I wonder if a bluetooth headset exists out there capable of switching between two or more preconfigured mobile phones.

Imagine it like a personal micro-telephone-exchange system: you receive calls at all your mobile phones with a single headset, able to switch between several conversations, possibly connecting them into a super-conference call – all carefree.

Even more fun it’d make having implemented voice control. I’d fancy it wouldn’t be too hard to add some logic for selecting an outgoing cellular terminal based upon called party requested (by voice dialing), time of day, etc.

That would be a perfect solution to the inconvenience of having multiple mobile phones on you.

Looks like there are quite a few multiple-phone bluetooth headsets most notable of which are Anycom BSH-100, Plantronics Discovery series i.e. 640, 645, 655 & Plantronics Voyager 510 (they’ve got “Multipoint Technology” connections), BlueAnt X3 Micro is even capable of switching between 3 phones.
Need to do further research on other features from my wish-list…