Any car built this century has an OBDII interface. This allows mechanics to plug in their laptop and get real time engine data. Lots of information about the running of the car. Nowadays there are quite a few USB / Bluetooth OBD-II connectors, which allow streaming of this data to your laptop, Garmin navigation system or iPod / iPhone.
Its dashcommand software ($40) allows you to create custom skins and settings for your own digital dashboard
It also sells a display unit
All these tools have different featuresets and support different cars…