One day every century, the numbers of the current month, day, year, hour, minute and second line up to match the first 10 digits of the mathematical constant pi: 3.14.15 9:26:53. On this page you can watch this rare event occur in real time. Only 100 years until the next time!
With the time displayed in 12 hour format, the digits will match pi twice; at 9:26:53 AM and 9:26:53 PM. And since there are currently 39 UTC offsets observed around the world, you will have 80 opportunities to catch the event! If you want a reason to extend the celebration by another 80 seconds, you may also include 9:26:54, since the 11th digit of pi is 5, which makes the 10th digit 4 when rounded up. 160 seconds of celebration spread throughout the day! Woohoo!
Although the pi second comes around on only one day each century, the Pi Day returns every year on March 14, which is also Albert Einstein's birthday.
Update: Some of our friends have reported that the seconds are highlighted "backwards". They are not. But when the hour shows 10, 11 or 12, the digits are shifted, and the seconds will match the 10th and 11th digits of pi (35) instead of the 9th and 10th (53).