Although there are many among us who tout the importance of Tau Day, the science, math, and programming communities tend to celebrate Pi Day every 3/14.
What are you doing to celebrate the day? Last year we created a program called Pi Eater to celebrate Pi Day 2013. The game challenges users to eat pie (pi?) as a means of learning the sine, cosine, and tangent of angles. In 2008 we competed to see who could memorize the most digits of pi, and one year our United-TI members regaled each other with tales of Pi Day celebrated in math class. About ten years ago, my high school math class celebrated 3/14 with Fig Newtons and Liebniz cookies in honor of the inventors of Calculus.
Happy Pi Day! Be sure to tell us about your Pi Day activities in the attached thread, and check out Pi Eater in honor of Pi Day below.