March 14th, often written as 3-14, is Pi Day! It's a day set aside to pay homage to the ratio of a circle to its diameter. The traditional way to celebrate is to eat a pie. Or bake one. Here are some wonderful Pi Day pies you might try this year.

ScienceBlogs, together with Serious Eats, held a Pi Day Bake-Off to celebrate Pi Day in 2010. Shown at the top is Claudette's amazing One-Hundred-Digit pie made with cherries, raspberries, blueberries, blackberries, and strawberries. Sure, it's not round, but remember, pie are square!

Serious Eats also held a Pi(e) Day Baking Challenge in conjunction with with Instructables in 2012. The winner was the apple Pi by Shannon. She cut the apples into number shapes with cookie cutters, and also cut the pie crust into numbers to decorate the top. And she posted the directions for doing so.

Instructables user dlgauthier made Mini Pi PIes, so that everyone at her office Pi Day lunch could have a whole pie. The pi symbol provided enough crust on the top of each.

Jessie Oleson of Cakespy created a recipe for Pi-Shaped Pie to celebrate Pi Day in 2011. This one is more of a big turnover, filled with chocolate and peanut butter. The instructions are at Serious Eats.

Instructables member hertzgamma took the idea of a pi-symbol-shaped pipe to the next level with a pie called "To 3.14 or not to pie." This one has cherry filling, but you can use any fruit filling. The lattice strips on top are engraved with even more numbers. She used a soldering iron for that part. If you feel up to this project, all the steps are laid out at Instructables.

Maybe you prefer your pies fried. If that doesn't sound yummy to you, you probably haven't tried a real Southern homemade fried pie! Instructables member starshipminivan made Fried Pi Pies for Pi Day 2010. This one has a chocolate filling, but you can put your favorite flavor inside.

This creative pie dates back to 2004, from Flickr user Jhayne, and has become a classic. The crust is shaped like a book (a math text, no doubt), and the first 24 digits of pi are carved out of the cover, letting us peek at the apples inside.

What you see here are 101 mini pies, adorned with one digit each, arranged in sequence showing pi to 100 decimal points. But look closer: even in that exact arrangement, there is a pi symbol visible among them. Instructables member brooklynbrownie plotted them all out before she began baking. The recipe has directions for three different fillings: caramelized mango, strawberry/raspberry chai, and blueberry.

A cookie for Pi Day? That seems so wrong, but it's okay, because this cookie is made from pie crust! Instructables member craftknowitall tells how her mother made crisp cookies out of leftover pie crust and adapted the recipe by shaping that crust into a pi symbol. The topping is cinnamon sugar.

You can make things a whole lot easier on yourself by rearranging the pepperonis on a pizza (before baking) instead of putting a pie together, like this pizza from Flickr user Ludie Cochrane. Or better yet, have the pizza pi for dinner and your pi pie for dessert!

Mathemusician Vi Hart tried to make pi as easy as pie by making a pie. She ended up making two pies, because it's not that simple. Hart prefers tau to pi, which is fine, as I prefer blackberry pie to peach pie.