Here's more on that folding shower from a quick google search:
http://www.apartment80.com/folding-shower-from-supiot/
""Supiot, a french based company brought to the world several years ago a shower that has won several awards in various fields. As the name tells us, the Folding Shower allows for space saving once it is folded and the shower is not in use. This type of shower is a must have for places where living space is missing: small apartments, small bathrooms, studios, rooms, or garages.
The Folding Shower is easy to install, even on very light walls, without major work. Folding Shower’s design allows for simplified wiring networks – hot water and cold water are connected behind the back panel. It is available in various sizes and colors or decorations, as many as one’s mind can imagine.
To use the shower, all that you have to do is place the water panel on the ground, with the curtain positioned correctly, and let the water run. Easy and practical as 1, 2, 3. After the operation, the curtain needs a few minutes to drain and then the tray can be closed. An important aspect is the fact that even when closed, the shower is naturally ventilated. In case of prolonged absence Supiot recommends us to leave the shower unfolded.
From now on, remember to fold the shower when you are finished!""
The photo at the above link shows the placement of the drain line....above the floor connected to the pan via a flex pipe........No price...."inquire"
While searching.............how about this one from 1901 :
http://blog.modernmechanix.com/folding-shower-baths/