BluePower is a program that switches your bluetooth on when the phone is connected to the power adapter. When it's disconnected, the bluetooth goes off. Of course, you can always switch your bluetooth on/off yourself.

How to install? Download the CAB file at the end of the page. After install, soft-reset your device. Bluetooth should switch on- and off when you plugin your power adapter. The program has no GUI, so don't bother looking for it ;-).

Discoverable by default !!