In addition to being Einstein’s birthday, March 14 is also Pi Day: From Yahoo News:

This is a story about love. About inscrutable complexity and remarkable simplicity, about the promise of forever. It is about obsession and devotion, and grand gestures and 4,000-word love letters.

It is about a curious group of people with an almost religious zeal for a mind-numbing string of numbers. Actually one number, made up of a chain that is known – so far – to be more than one trillion digits long.

They are the acolytes of the church of pi.

And once a year many of them gather to talk about pi, rhapsodize about it, eat pi-themed foods (actual pie, sure, but so much more), have pi recitation contests and, just maybe, feel a little less sheepish about their unusual passion.

That day falls on Wednesday this year: March 14. Or 3.14. Obviously.

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The Exploratorium web site has a page about Pi Day, and a page of pi links.

Click here for a pi poster:

Upon closer examination 350,390 digits of pi are visible. Each line contains 600 digits of pi. The first 440 most commonly recognized digits are visible from a distance.

And finally, a pi song/video. It’s to the tune of Don McLean’s “American Pie. Here’s the web site of the writer. The video only has part of the song, but here’s an mp3 of the the whole song, and this link has the lyrics.