During this hackathon developers were asked to build a Windows 8 app that a specific topic: image processing.
Sounds interesting but you have only tweleve hours to develop such an app then present it to a jury composed of Microsoft engineers.
Unfortunately (as always) I had to find a team, I ended in a two members team with only another student while there were teams with dozen members! And yet I wasn't familiar whit microsoft technologies (i.e. windows 8 and visual studio).
Anyway, it was fun and I finished the hackhaton in time with a simple intuitive app for kids, it was working, no bugs :)