Sliderules
Alexander A. Alemi.
Sliderules are cool. I'm rather enamored with them.
I've collected several over the years. One of my favorite is my old Soviet KL-1.

Unlike a pocket calculator, it feels like using a sliderule helps you develop a better number sense, rather than rob you of one. An elegant weapon for a more civilized age.
Digital Sliderule
In order to ensure that I always have a sliderule at my disposal, I recently build a digital one, available at sliderule.alexalemi.com.

Zine
If you're new to slide rules, in keeping with the tangible, physical theme, I made a Zine that attempts to introduce how they work. You can read it here:

Or you can download a PDF copy that you can print and fold yourself.
If you want to learn more, there is an old book by Isaac Asimov, or a great 1957 Educational film.
Make your own
You can print your own using instructions in an old Scientific American article.
Or an innovated circular slide rule created by Ying Hum that can be printed and fit in an old CD jewel case.
Another option would be to 3D print your own. Alex Desilets created plans for a series of 3D printed sliderules.
