Celebrate Pi? Really? With its bogus factor of two infesting each and every equation? Simplicity and elegance, your name is Tau. http://tauday.com/

Numberphile's Pi playlist: highly recommended! http://www.youtube.com/playlist?list=PL4870492ACBDC2E7C

Actually, Pi day is next year on March 14th, 2015. It may also work today if you take into account only the first 2 digits after the decimal point, but it kind of defeats the purpose.

π is 3.1415926535, no mention of 20. And altho Americans use 3/14/2015, Brits use 14/3/2015 and Asians use 2015/3/14.

Best to say Pi day is every March 14th, from 15:00 to 16:00.

> from 15:00 to 16:00

That seems more like "Pi hour".

Happy Pie Day http://mashable.com/2014/03/14/pi-day-pie-recipes/

How to celebrate Pi day: http://www.wikihow.com/Celebrate-Pi-Day

Pi in The Sky from SXSW: http://i.imgur.com/9Ymx7gp.jpg