Up and Away
Up and Away is the current title of a large collaborative mod for Klei Entertainment's Don't Starve. It sets to add a multitude of new content to Don't Starve, including, but not limited to, a new world type, new monsters, new structures, new fauna, and whatever else happens to end up in the final version of the mod.
It resembles the "Jack and the Beanstalk" story, with quite a few twists to the normal tales.
The mod is currently in Pre-Alpha. This means that the mod is still in its infancy, and most of its content is not implemented yet.
For more information, check its slide presentation and its thread page in Klei's forums.