How the Nvidia Ruler Measures Up
Adafruit makes a nice ruler for a reasonable price:<p><a href="https://www.adafruit.com/product/1554" rel="nofollow">https://www.adafruit.com/product/1554</a><p>as did eevBlog:<p><a href="https://www.eevblog.com/projects/uruler/" rel="nofollow">https://www.eevblog.com/projects/uruler/</a>