Critical Mass is an event which is held two times a year in Hungary (as well as sometimes more often and at varying times around the world), where bicyclists and other self-propelled commuters take to the streets en masse to demonstrate that biking is a good way to commute. Budapest's Critical Mass grows by each event in size, last fall attracting 70 thousand bikers, this past day having 80 thousand riders throughout the day.
What's great about this event is that the Critical Mass Hungary community site runs all on Drupal for the past few years, and the community is happy about it. It is great to see all these activity helped by Drupal, especially that this fine system is used on many of the other local biker sites for bicycle trading, dispatch riders, bike camps and several bikers associations. Another good cause where Drupal helps build a better world!
Also special thanks for the biker community who brought in some money for our Drupal Conference Hungary 2006 and then bought a camera for the last Drupal Conference 2007 for the Drupal User Group to use. This allows us to post videotapes of the presentations we have at our user group events ever since.