OK, this isn’t news, we’ll get to that in a moment, but wow, check out this huge personal collection of slide rules, 143 rules in all. I guess you could call these an ‘old school gadget’.
If you’ve ever used a slide rule you’ll probably spend a minute or two browsing through this collection reminiscing. Ah, the good ole’ days. If you’re not familiar with how they operate, here’s a primer on the theory and operation of a rule.