Stunningly Intricate: Curta Mechanical Calculator

I've never heard of these but Dark Roasted Blend writes about Curta Mechanical Calculators.

"For years Curta calculators enjoyed a cult status among collectors, and as recently as in 2003 they were featured in William Gibson's 'Pattern Recognition' book. However, I daresay, not featured enough. This marvel of mechanical engineering should be given more exposure, especially given the bizarre and spooky circumstances of its origin."

- Entirely mechanical, no electricity or batteries involved.
- Designed by Curt Herzstark in 1938 and perfected inside a concentration camp.
- Considered to be the most efficient portable calculator (until electronic calculators came in the 70s)
- Simply a thing of beauty, stunning piece of engineering art.

This thing is amazing...