Today is 3/14, better known to the math-loving community as Pi Day, an international celebration of the irrational number and, for some, its almost-namesake dessert. In honor of the occasion, the iconic logo on the Google homepage has transformed into a collection of formulas that use pi. To celebrate, write a "pi-ku" poem—three syllables, one syllable, four syllables—or just wish Albert Einstein a happy birthday.
(More Pi Day stories.)