We've seen tanks, musical instruments, DSLR add-ons and, of course, gaming consoles built out of the wonderful little Raspberry Pi, but the BrewPi is the best invention of the lot. Beer brewing automated thanks to the Pi? Pure genius.
Using the Pi and an Arduino, a homebrew enthusiast developed an open-source fermentation controller, which allows you to control the whole process from the comfort of your web browser.
It's completely customisable too, and will control the temperature down to 0.1 degrees Celsius. It'll also spit out a load of fancy graphs to make you look like you know what you're doing while its at it. Pi homebrew has never been so golden and delicious. [BrewPi via Raspberry Pi Foundation]