A side project I did with @joannava for a contest called abredatos, whose purpose was to create tools that exploited public government information sources in a useful way.
It was a search engine for public servant job positions. You could subscribe to certain search terms from RSS or email news-letter and get alerts whenever an offer of your interest was published.
I did the design and frontend side, and Joan did the backend side.
A great hackathon (1 week) experience.