Now here’s an SF idea from the post-cyberpunk era–something out of Sterling, Stephenson
There’s lots more images and details over at Inhabit.com, but the basic idea is that the ongoing rise of urban density (presumably driven by increased fuel prices and the hollowing of the suburbs) will mean we can’t afford to waste space. So we attach “parasitic” structures onto the sides of previously unused vertical spaces.
And, of course, to make it all Viridian, the attached structures are custom designed for each installation, but built from pre-fab and eco-friendly components.
There’s lots of other interesting and SFnal stuff at the site, including the pod homes, and the urban homes built atop forests the clean contaminated soil, etc.
It keeps getting harder to tell SF from the real world.