Vibs had recently blogged about sky villas which are "by invitation only".Interestingly, looks like its not just the sky, but also the sea where villas will come up in the near future making sci-fi become sci-tru :).
Trilobis 65 is one such submerged dwelling environment or simply a floating home.
Italian naval architect Giancarlo Zema who designed the part yacht and part submarine says " "The main aim of the project is to allow anyone to live in a unique environment through a self-sufficient, nonpolluting dwelling that exists in unison with their ocean surrounding"
Read more about the Trilobis 65 here.