Backend for the JuliaDroid app for Android.
This is simply a basic API, that accepts expressions in Julia, passes them to a Julia interpreter using node-julia, and simply passes the result back as a basic JSON object. Currently, it's supposed to be used with the (JuliaDroid)[https://github.com/rudimk/juliadroid-app] app for Android, but you can use it anywhere.
To run this API, you're going to need Express, and node-julia, along with a working Julia installation on the same machine. Then, simply fork the repo, run npm install inside the repo directory to update your node modules, and run node app.js.
This was built in a 5-hour nocturnal pizza-plus-Tzinga-fuelled session at the Hacknight for Droidcon India 2014. But I am thinking of a lot of ways in which to take this further. Adding support for passing Julia scripts from a client app to the API, marshalling datatypes, even support for SVG plots, as well as user auth and tracking user computing metrics(whatever that means), which can be rendered on compatible clients - all on the roadmap.