OSCON keynoter David Heinemeier Hansson just launched The New Rails Movie. It’s a walk-through of building a blog engine with Rails. Whether or not you think Rails is the bee’s knees and the wasp’s nipples, you have to admit that the 37 Signals crew are master marketers. In many ways, more amazing than the technology of Rails is the way these guys have created buzz and build a community by lowering barriers to entry. They have lots of documentation, a happy vibe on the community forums, and quickly created an active and passionate user community.