This event was run by the Environment Agency and held in Bristol. It was linked to their announcement of opendata releases of key datasets.
I hooked up with a group to explore the circular economy. The coding was a bit disjointed as we had a team member adamant that we use JSP and then dropped out after the first day. I rewrote it in my hotel room that evening in Ruby on Rails and got the whole thing done. On a hack day, the coding shouldn't really get in the way of expressing the ideas.