You do not need this pi day to make that pie. Thats an everyday pie and my math adds up all the way to my mouth!! Im hungry...
At one time, I had a pocket protector and a slide rule I wore on my belt. In fact, I've had at least three slide rules, one bamboo, another metal and a third was a circular slide rule made out of heavy paper. My senior year in engineering we had a slide rule throwing contest at a local pizza parlor. We all tossed our slide rules into a waste basket from about 30 feet away. Wish I'd kept mine.
I had a circular slide rule in college. Kept it for years. One night leaving work an asshole snatched my bag, got my slide rule which I'm sure he really wanted.
I think I got mine out of a publication of Spectrum, the magazine put out by the IEEE (Institute of Electrical and Electronics Engineers), the largest professional organization in the world of which I was a member for many years.