It was pi day yesterday. March 14 is the day because if you write the date 3/14 then you have the first 3 digits of pi.
Some light hearted information about pi from wikipedia:
The value of π has been computed to more than a trillion (10^12) digits (source).
The Guinness-recognized record for remembered digits of π is 67,890 digits, held by Lu Chao, a 24-year-old graduate student from China. It took him 24 hours and 4 minutes to recite to the 67,890th decimal place of π without an error.
There are many ways to memorize π, including the use of "piems", which are poems that represent π in a way such that the length of each word (in letters) represents a digit. Here is an example of a piem, originally devised by Sir James Jeans: How I need (or: want) a drink, alcoholic in nature (or: of course), after the heavy lectures (or: chapters) involving quantum mechanics.