Portable speedometer? Is there such thing, and can you give me a link?

Question

The mechanic said it was hellish to fix the speedometer on the car. Is there a portable one I can buy and, like, mount on the dashboard? I dunno how these things work.

Answer 1

you can use an aftermarket gps or pocket pc with this software  http://www.tchartdev.com/gps_speedo.htm