Japanese lodging operators seem to never run out of new ideas to shake up the field, and this one is no exception: A Tokyo hostel that used to be a sleeper train that linked the city to Sapporo, in Japan's north.
When the Hokutosei (which means Big Dipper) was taken out of service in 2015, the sleeping compartments were salvaged, and installed in a Tokyo building to become the Hokutosei Hostel, with 4-person compartments, some mixed gender, and semi-private compartments.
While it no longer goes anywhere, it is still connected to the railroad adventure; the building it's in is attached to Japan Railways' Bakurocho train station. The hostel also includes a cafe equipped with equipment from the train's dining car.
Or, if railroad chic is not your thing: Have you considered sleeping in a bookstore? Another hostel offers that opportunity, with hundreds of books available, as well as special sleeping shelves for guests.