I saw this article in popular science's 'HOW2.0' and just thought it was so cool; I couldn't resist. I did not create the code or design. Credit to this project goes to the code authors listed in the Arduino sketch, and the authors/creator(s) listed on the PopSci page. Info on this project here: Build a gas guzzler meter | Popular Science. Pictures of the finished/semi-finished product I made are below.
All of it in the case:
The exterior:
Innards:
PCB traces:
