Yes folks it's that time of year again. GO DO SOMETHING IRRATIONAL!!!

From WikiHow:


Pi Day is a special day in the lives of many-a-nerd. Just like normal people celebrate Valentine's Day or National Pancake Day, nerds around the world will gather and join hands in the shape whose ratio of its circumference to its diameter is the most revered mathematical constant in the known universe. Below are some tips on making this day (celebrated on March 14 at 3:14pm) memorable to one and all.
Steps

1. Create some pi ambiance. Just like people display a tree and mistletoe, wear Christmas gear, and sing Christmas songs around Christmas, there is a lot of room for making the environment around you reminiscent of pi. Probably the favorite of most is to wear a pi t-shirt--this idea can be taken further to include pi jewelry (maybe a necklace whose beads represent the numbers in pi), a pi mug or clock, or other pi paraphernalia. Beyond just apparel, though, make your computer wallpaper into something related to pi, change your ringtone either to actual "pi music" or to a song that reminds you of the famous irrational number ("American Pie", for example). Another step is to change your internet homepage (you should have the internet if you're reading this) to a 'pi page'. See the links at the bottom for a few different ones.


2. Convert things into pi. This step is absolutely necessary for two reasons: To utterly confuse people who have no idea what you are talking about (thus opening the door for enlightenment) and to have fun seeing how many things can be referenced with pi. Consider two approaches:

* Convert naturally circular things into radians like the hours on the clock. Instead of it being 3 o'clock, now it's 2*pi o'clock. Or, instead of it being 3 o'clock, convert the inclination of the sun into radians and describe that as the time.

* Simply use 3.14 as a unit of measure. Instead of being 31 years old, you are 9pi years old (approaching your 10th birthday). With this same approach, you can find out your next pi birthday (don't forget to celebrate it when it comes!).


3. Play pi games and make strange mathematical endeavors. These are in the same step because many math nerds consider them the same thing. There are plenty of traditional games that are appropriate on Pi Day, like a pinata, a pie-eating contest or pie-in-the-face fundraiser, etc. Of course, being nerds, there are more intriguing things to do like writing a pi-ku or pi-em, holding a pi memorization or recitation contest, discussing different ways to derive pi, seeing who can write pi in the most noticeable (though legal) place on campus, at work, etc., calculate the average error experienced when using 3.14 as an approximation, finding your name, birthday, ATM pin, etc. in pi, finding pi in pi, or discussing what things would be like without pi (the earth being a square and so on). This list could literally go on and on; hopefully this is enough to give you ideas of your own.


4. Eat pi foods. Many creative ways exist to do this. First, there's the punny approach, like eating pineapple, pizza, or pine nuts and drinking pina coladas or pineapple juice. Second, there's the shape approach, like making cookies or pancakes shaped like pi or making a pie with a pi cut out of the center of the crust. Of course, whatever you do, Pi Day is simply incomplete without eating pie, even if you don't feel artistic enough to carve the pi symbol out of the top.


5. Do a pi mile run. Go on a run for pi miles, which is just over a 5K. You can take this a step furthur by organizing a pi mile run.


6. Help the tradition continue. Don't let this be a one time thing--you owe it to pi to celebrate again and again. Set the date for next year and maybe create a pi club or website in the process. Celebrating Pi Day is just as easy as pi (sigh).


Tips

* Pi is 3.1415926535897932384626433832795028841971693993797150... This number continues indefinitely, and so far has been tracked out to 1,241,100,000,000 (over 1 trillion) digits after the decimal place using a computer. There are regular competitions to see who can remember the most digits.

* Pi approximation day is also celebrated, though less widely. In the international date format this is July 22 (22/7); the 355th day of the year at 1:13 (based on the approximation of 355/113) or November 9/10, the 314th day of the Gregorian calendar.


Warnings

* There is some debate regarding the exact time that Pi Day should be celebrated. Whilst the 1:59PM stated above is probably the most common; it is also claimed that the 24 hour clock should instead be used, and Pi Day celebrated at 1:59AM or 15:09PM.

* If you don't use the American date format, Pi Day instead corresponds to January 3 at 4:15.