Bonus points for recognizing this:
Not only is today pi day (3/14), it’s uber pi day: 3/14/15. (Also note the time of this post.)
There are many ways of celebrating pi day, many of which include consuming lots of circular foods. This makes sense (as pi is the ratio of the diameter of a circle to its circumference, for the nerd-impaired.)
Many people also like to get together and play games (hence the double entendre of the above cookie design), which doesn’t really make much sense.