Let me first say that the free beer mentioned in the title is really an homage to Richard Stallman's quote to explain what free software is -- "you should think of 'free' as in 'free speech,' not as in 'free beer.'" Some people decided to have a little fun with the quote, though, and they've taken the free and open source philosophy to the beer making industry. Whether it's a community-created and -maintained recipe or one that's free to use, alter, and reshare, brewing will never be the same. And if you're a homebrewer looking for some new ideas, there are lots of free and open source recipes out there for you to take advantage of ... so hop(s) to it!
It only seems fitting to start our list off with the first beer marketed as free and open source, Free Beer. But being open source isn't the only unusual thing about this brew -- it also contains a little caffeine to help fight the drowsiness that can come from drinking beer. Maybe it was the fact that one of the founding groups was made up of college students from Copenhagen IT University, but, according to their website, they decided to add South American Guarana beans to act as a "natural source of energy and health." You can't, after all, let a night of studying get in the way of enjoying a beer or two, right?
The other co-founding group was Superflex, an artist collective based in Copenhagen, and they've actually taken over the project. They also changed the name to Free Beer (it was originally called Vores Øl, which translates to Our Beer), and they were pretty active in trying to spread Free Beer around the world. Their blog hasn't been updated since 2010, but the recipe and labels are still online and available for use ... just make sure that you follow the rules of the Creative Commons Attribution-ShareAlike license that it's under.
Le Baiser de la Princesse
And in true open source fashion, the next beer on our list is a derivative of the Free Beer recipe above. Started by another group of students, Le Baiser de la Princesse (which translates to Kiss the Princess) began as a project in the Knowledge & Information Services (KIS) section of Ecole Polytechnique Fédérale de Lausanne in Lausanne, Switzerland. According to the official beer website, it was created to allow the students to take an idea from inception to completion, and although it was temporarily dropped as a project, it was restarted in 2008.
Yeastie Boys' Digital IPA is a little different than the two open source beers above, partly because it was created by a brewery, not a group of university students. Yeastie Boys is located in New Zealand, and although not all of their beers are open source, there is one that makes the cut -- the Digital IPA.
The recipe has been released under a Creative Commons license, and as long as you give credit back to Yeastie Boys, you're free to use, change, and share the recipe and even sell any beer you brew with it. Plus, if you're buying the official beer, you'll see that there are six QR codes on the label that let drinkers get the recipe and comment about the brew, ultimately helping Yeastie Boys improve the recipe. Those changes are all coming back from the community, helping to solidify Digital IPA's open source credentials.
More Beer Geekiness
And if you're looking to increase your homebrew reputation and push your geek score up, don't worry -- the free and open source community hasn't let you down.
If you're more interested in creating your own recipes rather than using ones that are already out there, Brewtarget could not only make that easier for you, it could also help you stay a lot more organized. According to the official SourceForge site, "The ultimate goal of the project is to be able to take a set of user-given constraints and immediately formulate a recipe," helping users with calculations and recipes. The open source application works with Linux, Microsoft Windows, and OS X, and implements BeerXML.
And finally, if you're searching for an open source hardware project, why not check out BrewPi: The Raspberry Pi Brewing Controller. Built on RaspberryPi, it'll have you homebrewing open source-style in no time. Not sure what RaspberryPi is? Check out Open Source Hardware for Hobbyists for all the details.
Whatever your interest level is in brewing beer and no matter what your skills are, chances are that there's an open source project that can help you along the way.