Please propose topics for the Amsterdam Hackathon here:
https://www.mediawiki.org/wiki/Amsterdam_Hackathon_2013/Topics
This is specially useful when there is various people intending to go to Amsterdam to discuss and work around a specific topic.
For instance, I have heard a couple of people mentioning the possibility of running a Design workshop. Listing this topic there is useful, as it will make the organizers and other potential attendees to consider.
Thank you!