This project is a bit different from what I normally do. No firmware to write, just several trips to the hardware store and a lot of quality time with the drill, files, and nibbler. But this one has a higher purpose: Food.
It was actually a commission by a friend of mine. He wanted to try sous-vide cooking, but neither of us were crazy about the idea of paying for something lab-grade, and even the consumer-focused SousVide Supreme seemed kind of lame with its $450 price tag and no circulation pump.
The interwebs are brimming with do-it-yourself solutions for sous-vide cooking, ranging from the incredibly simple and cheap, through a middle-ground of modified rice cookers and crockpots up to other DIY immersion circulators like this project by Scott at Seattle Food Geek.