York, Alabama
Looking straight on, it appears to be a little house.
Then, one sees the ‘arms’ to each side 
This is artist Matthew Mazzotta‘s Open House, 2013 in York, Alabama
It unfolds to make a space with built-in seating area. From the press release:
The metamorphosis of Open House is designed to require cooperation. It takes four people one and a half hours to unfold the structure. The foundation is made of used railroad ties which anchor the custom fabricated industrial hinges to five rows of stadium seating. The rows of seats fold down with the aid of a hand winch and enough manpower to counter balance the hefty, but agile structure.
Critical Impact
Through the project, the artist hopes to directly address the lack of public space in York, AL by providing a physical location that becomes a common ground for community dialogue and activities. The new structure carries the weight of the past through the materials that were salvaged and repurposed from the old structure,most visibly the original pink siding. When Open House is fully unfolded, it provides an opportunity for people to come together and experience the community from a new perspective. When it folds back up, it resembles the original abandoned house, reminding people of the history of what was there before.
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Similarly, his Storefront Theater in Lyons, Nebraska
Interesting: Cloud House