Inside NYU art professor David Darts' black metal lunchbox, painted with a white skull and crossbones, is the PirateBox - a tiny Linux server, a wireless router, and a battery. Turn the PirateBox on and you have a self-contained mobile communications and file-sharing device, whereby those in the vicinity can upload and download files securely and anonymously. (See this 2011 Ars Technica story for photos and details.) Built with free and open source software and openly licensed itself, the PirateBox has inspired a number of other projects, including Alan Levine's Storybox and now Jason Griffey's LibraryBox.
ArduGate: a web gateway for Arduino that makes possible to use JavaScript inside the web browser to interact with Arduino. Currently available just for Windows, however, release for Linux and MAC OS X will be available soon.