https://www.youtube.com/watch?v=UxUZIHAJ2H4
The Interactive Woodland at Royal London Hospital produced by Nexus really shows how the idea can be refined with beautiful designs by Felix Massie, and also great use of the space with the giant chairs and television. So much fun.
One of the fascinating things about our childhood perception is the the compression or expansion of space: under the table becomes a den; between the couch and the TV becomes an ocean. That idea is implemented here nicely. I wanna play too!
http://www.nexusproductions.com/latest-news/2013/02/interactive-woodland-at-royal-london-hospital/