The Ubertooth One is an open source 2.4 GHz wireless development platform suitable for Bluetooth experimentation. Based on the powerful LPC175x ARM Cortex-M3 microcontroller with full-speed USB 2.0, the Ubertooth One is a great way to develop custom Class 1 comparable Bluetooth devices.
The Ubertooth is able to capture and demodulate signals in the 2.4GHz ISM band with a bandwidth of 1MHz using a modulation scheme of Frequency Shift Keying or related methods. This includes, but is not limited to Bluetooth Basic Rate packets and Bluetooth Low Energy (Bluetooth Smart).
You can use Wireshark network protocol software to analyze Bluetooth traffic.
More information is available on the website of Sparkfun and GSG.