Instead of replacing the broken speedometer in his Ford Mustang with an identical unit, Instructables user "TankMorph" instead took the Arduino path and created a useful information centre for the replacement. Using a GPS, temperature sensors, a real-time clock and associated hardware the system can not only display speed, direction, the time and date as well as keep track of distance and trip meters, it can also control cooling fans and more. Although a work in progress, you can examine the sketch and see how it's all working. And when used with a 20x4 character LCD display, the results are quite professional, for example:
Just goes to show what you can do with some inexpensive sensors and an Arduino. Visit the project page for more details and the sketch. And for more, we're on twitter and Google+, so follow us for news and product updates as well.