Pete Docter is really embracing his next film, Up (due for release May 29, 2009), by putting part of his house ‘up’ in the air in a treehouse. The San Jose Mercury News is reporting the story and says,
"He and his wife bought 15 acres of secluded, vacant land in Lafayette and proposed a 60-foot-tall artificial oak tree with three treehouses. A suspension bridge would link them to a new house on the adjacent hill. An elevator would connect the house to a garage 25 feet below, burrowed 80 feet into the hillside."
The Pixar Blog have done a bit more digging on this story and show aerial photos of the land as well as concept art for the houses including the above right image.