Package blueproximity

Detects you via your bluetooth devices and locks/unlocks the screen

http://blueproximity.sourceforge.net/

Add security to your desktop by automatically locking and unlocking
the screen when you and your phone leave/enter the desk. Think of a
proximity detector for your mobile phone via bluetooth.

General Commands (Section 1)
blueproximity
blueproximity helps you adding a little more security to your desktop. It does so by detecting one of your bluetooth devices, most likely your mobile phone, and...