If an Ewok and a Hobbit collaborated on a house together, this passive-house design by Robert Oshatz for a Portland residence may be what they come up with.
A one-of-a-kind concession stand in Indiana is, at once, a work of art, a functional green building, a science exhibit, a recreation area and a respectful lesson in resource conservation and life cycle analysis.
The Cocoon Tree is a lightweight tree house pod you can rig up yourself in your own backyard in around two hours, but camp out in (and nap in) all year long.
The 6th Layer Explorative Canopy Trail creates a kind of super-sized hammock amid the treetops of the Amazon, allowing for exploration with minimal impact.
Free Spirit Tree Spheres, located on five forested acres on Vancouver Island, British Columbia, offers novel accommodations for eco-travelers amid the treetops.
Finca Bellavista, billed as the first modern, sustainable tree house community, offers eco-lodgings and treehomes in Costa Rica, with a conservation ethic.