We've shown off some great things you can do with the Raspberry Pi, but if you're a homebrewer and want a way to easily monitor your mash, this project is for you. Lifehacker reader Sebastian built a Pi-powered controller to monitor and even adjust the temperature accordingly.
Of course, you already have to be in pretty deep with homebrewing to really manage your mash to this degree, but using a Raspberry Pi to monitor your mash's temperature and make adjustments along the way gives you an easy way to check on its health and keep an eye on the fermentation process. Here's how Sebastian describes it:
MashBerry is a Raspberry PI based beer-brewing controller. It is designed to automate the mashing-process for the homebrewer. MashBerry can be operated via a Web-interface or via a Display and an IR-remote. The temperature is controlled using a PID-controller, the temperature-measurement is done with a PT1000 or a Dallas 18B20. For power-control an external Solid-State-Relay is used.
The whole configuration (like entering recipes, PID-Autotuning, etc.) is done via the built in Web-interface.
The ability to keep your Mashberry in a nice, dark place (where it should be) and check on it via a web interface is a nice touch, and Sebastian notes the entire project is open source and GPL licensed, so if you'd like to borrow, tweak, or improve, you're free to do so. He lists all of the parts you'll need and the software to run the whole thing at the project link below.
MashBerry [Sebastian Duell]