If you are reading this I suppose you are already familiar with GMLAN. In short, GMLAN is a communication protocol based on CAN-BUS to send data between different Electronic Control Units (ECUs) in the car like BCM (Body Control Module), IPC (Instrument Panel Cluster), EHU (Entertainment Head Unit) and so on. GMLAN is a single-wire CANBUS protocol (SWCAN) with 33.3kbps baudrate.
The only thing I wanted was to sniff steering wheel radio commands and send them to control my CarPC, but this turned out very interesting for me to think of other possibilities and ways to make my car smarter.
More details at Dimitar’s blog.