Facebook engineers held 12 hackathons last year which led to some fun, offbeat projects.
A "hackathon" is the techie version of brainstorming. Instead of just jawboning about some off-the-wall idea, they go ahead and code it.
Today the team revealed their favorite hackathon projects on the Facebook Engineering page.
We have to admit we're impressed. Here are the five we liked the best:
1. In their very first hackathon of 2012, having just moved into their new Menlo Park, Calif., campus, they painted a giant QR code on the roof of a building. It originally pointed to a spoof listing for a "QR code painter" job, but now points to a page about the project.
Can you spot the code in this aerial shot of the campus?
2. Engineer Paul Tarjan mapped out data about which users liked which NFL teams' Facebook pages across the country, and found out some surprising things—like how the Upper Peninsula of Michigan has a lot of Green Bay Packer fans, instead of being loyal to the Detroit Lions.
3. Using open-source hardware from a company called Arduino, the team built a display of flashing lights which warned about spam levels on Facebook. In addition to email alerts, the spam fighters now get red, yellow, and green lights telling them when they need to step in and do battle.
4. Tin Tse, Veerendra Mulay, and others submerged a computer server in oil to keep it cool. It worked. The servers ran fine at temperatures above 110 degrees Fahrenheit.
5. Benjie Holson from the Timeline engineering team printed a 3D object that mapped where in the world people use Facebook. It looked like a spiky crystal—handle with care!
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