There is geek chic and now retro geek chic. If you are a rocket scientist, the requisite computing instrument of choice is the slide rule. Wearing it like a sword has become impractical and unfashionable. Now just wear it on your arm.
Slide rules are simple devices that can do some very complex mathematical calculations. They put into use some of the theory you learned about logarithms in high-school algebra.
The Slide Rule Museum has a template to make a model slide rule. I took that and transformed it into a piece of functional jewelry.
This will be made entirely from paper/cardstock
Note that accuracy of the instrument is limited to the medium, construction method, and skill of the operator.