CAN Bus
From Wildsong
See also 8track
CAN interfaces
Pi-CAN http://raspberrycan.blogspot.com/2012/08/controller-area-network-can-mcp2515-for.html
eDash
Circuit Cellar article: eDash Robin Brophy Sep 2011 issue 254
microOBD
Sparkfun UBM32 controller: USB 32-Bit Whacker - PIC32MX795 Development Board $40
320x240 LCD
SD card