It may sound bizarre at first but Yamaha’s portable rooms, dubbed myroomII [JP], do make sense. Yamaha says it’s the perfect product for all people wanting some alone time without having to move into apartments with more rooms.
In the product catalogue [JP, PDF], the company suggests watching movies, working on your PC, reading, studying, Karaoke, listening to music and playing instruments as the main examples for use. The room could be especially useful in Japan (where it’s available exclusively at this point), where apartment buildings with super-thin walls are not really rare.
The myroomII is made of dark wood, soundproof, air-conditioned, pretty heavy (340kg) and quite big (1385×1826×2065mm). One room costs $7,000.