Need an idea for what you could do during hgcn.de meetup? How about breaking the surfing world record?
South African surfers broke the Guinness World Record for the most surfers riding one wave simultaneously at Muizenberg Corner, Cape Town, South Africa, 04 October 2009. The new world record - 105 people surfing one wave simultaneously.
If all of hgcn.de visitors gathered in one place, you could try and break this record.