Yesterday I opted to write about Stab Your Friends in the Back Day, but neglected the real holiday that actually occurred Sunday: Pi Day.

Pi Day is a holiday for math geeks and technies and it’s also a great opportunity for math teachers to teach their students about pi, one of the coolest strangest numbers around. It’s also Einstein’s birthday.

It’s a shame it fell on a Sunday.

I suppose we could have celebrated it by getting irrational.