I built a computer vision device that used the top-down area of a penny as a calibration standard. Coins are useful, easy-to-get items that have relatively tight manufacturing tolerances.
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Of course there's a limit to the precision you can get from coins, but considering the scale of their production and the account of handling they see they are surprisingly good
We use a pack of cigarettes as a gauge for one of the jobs we do. Quick, (not so) cheap, and readily available. May have to standardize on a vape though in the near future.
It's been happening since ever.