Gohei Hayashi of Kyoto University is seen in side his movable eco and healing house, “Kujira (Whale) House” July 21, 2007 in Tokyo, Japan. The house is made from Japanese paper, bamboo and tatami mat. Hayashi has travelled 500 km from Japan's ancient city, Kyoto to Tokyo with his eco house to promote his house which can be placed both out inside and outside to provide a private space. The Kujira house is available at the price of 800,000 yen (roughly US$6600). (Photo by Koichi Kamoshida/Getty Images)

Colorado Gov. John Hickenlooper shows off his socks--one with Democratic presidential candidate Bernie Sanders and the other with Republican candidate Donald Trump – before entering his former brewpub for a book signing event to mark the release of his autobiography Thursday, May 26, 2016, in Denver. Hickenlooper, who is term-limited, is doing book talk rounds this week, reviving speculation that he is positioning himself to join Hillary Clinton's presidential campaign ticket. (Photo by David Zalubowski/AP Photo)

A Palestinian female volunteers for the al- Aqsa Martyrs Brigade, a militant group part of Fatah movement, stands with her weapon in this undated photo. Unlike Hamas and Islamic Jihad, the ideology of al-Aqsa is rooted in Palestinian nationalism not political Islam, and is the only Palestinian group that accepts and trains women to be “martyrs”. (Photograph by Courtney Kealy/Getty Images)

“The World Stands on its Head” (“Die Welt Steht Kopf”) House on the Baltic Sea Island of Usedom stands nearly completed on September 3, 2008 in Trassenheide, Germany. The upside down house, complete with upside down interior furnishings, is the brainchild of Klaudiusz Golos and Sebastian Mikiciuk, and will become a local tourist attraction. (Photo by Sean Gallup/Getty Images)

The images of U.S. Democratic presidential candidate Hillary Clinton (L) and Republican Presidential candidate Donald Trump are seen painted on decorative pumpkins created by artist John Kettman in LaSalle, Illinois, U.S., June 8, 2016. (Photo by Jim Young/Reuters)

Kha Tu Ngoc rests in her two- square- meter house in Ho Chi Minh City on May 2, 2018. The “micro- house” dwellings are dotted throughout Vietnam' s bustling southern hub, occupied by families clinging to postage stamp- sized plots a city developing at breakneck pace. Tucked away in winding alleys, nestled under new condo developments or sandwiched between street food stalls and shops, the tiny houses are easily missed by the unattentive passerby. (Photo by Thanh Nguyen/AFP Photo)

Bonbibi, Treehouse Point, Fall City, WA. The Bonbibi is balanced on two steel yokes. The yokes spread out the load and allow for tree growth and movement in the wind. A small deck hangs from the beams below and uses the treehouse itself to shelter guests. (Photo by Pete Nelson)