The Thirteenth Room

For his or her latest project, a well-known (but not necessarily well-liked) artist convinces a number of architects – from dRMM, ECDM, and Vaillo + Irigaray, to SOM, mos, Beckmann N'Thepe, and INABA – to include in some future building a small room that the artist herself has designed.
It's the exact same room, and it will be repeated again and again, throughout numerous structures around the world – but it will be done without any public acknowledgement that the rooms exist. It's an art project no on knows about.
These rooms' presence inside the buildings will thus be kept a secret; no one will know that they exist, let alone where they all might be.
A hotel in Barcelona, a library in Wales, a private home somewhere in Midi-Pyrénées, a pharmaceutical HQ outside Singapore: these and other projects all contain a room.
Within a year, reports surface on various travel blogs about intense spells of déjà vu experienced by visitors to one or more of these buildings.
Gradually, urban myths even appear – and soon Nick Paumgarten of The New Yorker reports on the rise of something called the "room-detection industry," researching whether or not certain buildings contain identical internal spaces.
It's all very strange and a discussion quite limited to the world of global frequent flyers; the art world, understandably, takes no notice of these rooms at all.
But then the project is revealed a decade later, unexpectedly, in an exclusive interview with Artforum. All ten rooms have been installed, and their locations are made known, complete with an interactive map posted on artforum.com; one of the rooms, however, was demolished in 2011 when the building it was in was taken down (...or was it?, PhD students ask, writing term papers at Princeton).
Many people are amazed by this story; most people don't really care, considering it pure wankery.
Some, however, are thrilled beyond imagining, having themselves long suspected that they might have encountered this very project – a room at the Tokyo airport, or deep inside an outer London convention center – but they had simply filed it away as faulty memories.
But it was real: they really did experience the same environment twice, with no explanation, inside two radically different buildings on opposite sides of the planet.
However, reports of further rooms begin circulating, literally as early as the comments thread on the interview. People simply do not believe that the project is over. There's an eleventh room, some say, in a Seattle hospital – and they've got photographs to prove it. There's a twelfth room in Morocco; a well-known journalist claims to have been there just last week.
Then the knock-offs begin to appear: illegally pirated interiors designed to fool the wary.
None of which would really have interested you, had you not yourself just opened the door of a temporary flat-sit in Sydney, where you'll be for the next two weeks, only to drop your bags to the floor in sheer wonderment.
You've seen this room before..., you realize. It's the thirteenth room...