Happy Tau Day! The Tau Manifesto by Michael Hartl is now available in print, if you’re in the market for a particularly nerdy coffee table book and conversation starter:

I also wrote about Tau Day ten years ago; see that post for more links! Using we can make the most beautiful equation in the world even more beautiful:

Please enjoy eating two pi(e)s today. I’ll be back soon with some solutions to the parallelogram area challenge!