I was skimming through one of my favorite magazines called Architectural Review, and I noticed a really cool article entitled "Tubular Troglodytes." I couldn’t find the article online, but I did some research on the architect and discovered a hotel in Linz, Austria with the name of dasparkhotel. Some of the website is in German, so I found the Google Translator somewhat (not completely) helpful. From what I understand, Dasparkhotel is a concept creation of Andrea Strauss.
As far as accomodations, this place isn’t that bad! You get a double bed, fresh blankets (or sleeping bags–can’t tell from the translation), lighting, moon/day light hole in ceiling, stow-a-way space beneath the bed, 220 V power connection, and an internet connection. Further, the surrounding area has toilets, showers, and a minibar & cafe.
Each tubular hotel room was created with redesigned, standardized sewer pipes, with a diameter large enough for normal people to stand up. Reservations for a "room" can be made online, and you use a code received via email to access the room. Apparently, the pay rate is "pay as you wish." I couldn’t discover whether the surrounding area services (toilet, minibar, shower, & cafeteria) were "pay as you wish"–meaning if you use it, you pay for it–or the actual hotel tube was "pay as you wish"–choose the amount and pay it. Regardless, I think this is a great idea!