BlueMaho is GUI-shell (interface) for suite of tools for testing security of bluetooth devices. It is freeware, opensource, written on python, uses wxPyhon. It can be used for testing BT-devices for known vulnerabilities and major thing to do - testing to find unknown vulns.
BlueRanger is a simple Bash script which uses Link Quality to locate Bluetooth device radios. It sends l2cap (Bluetooth) pings to create a connection between Bluetooth interfaces, since most devices allow pings without any authentication or authorization. The higher the link quality, the closer the device (in theory).
Bluepot was a third year university project attempting to implement a fully functional Bluetooth Honeypot. A piece of software designed to accept and store any malware sent to it and interact with common Bluetooth attacks such as "BlueBugging?" and "BlueSnarfing?". Bluetooth connectivity is provided via hardware Bluetooth dongles.