Well, Since I have a tight budget I'm allways thinking of ways to transform stuff. Latest gizmo on my bug... Electronic digit Speedometer for 15 euros. How? Just use a bike speedometer :) Yap! It works, and it's super-precise! (tested comparing with GPS speed). All you need to do is attach the sensor on the front weel support (same weel of the original speedomenter cable by coincidence) and glue (fiberglue) the little magnet to the drum close enough to the sensor.
MM