You can listen in on a two meter repeater and you can build a GPS module speedometer. That’s what [Jeremy Cook] did with just a few parts, a little 3D design, and some handy zip ties to hold it ...
[Ah2002] didn’t like the shaky needle in his car’s speedometer so he replaced it with a ring of LEDs. The old speedometer had a cable which rotated along with the gearbox for mechanical speed ...