Word has it that Google has been sniffing around the idea of tapping into Dark fiber - fiber optic cable that's already been laid, but is not yet in use. There are literally thousands upon thousands of miles of dark fiber is available in the United States, the potential for which is pretty staggering. Google seems interested.
"Google is looking for Strategic Negotiator candidates with experience in...(i)dentification, selection, and negotiation of dark fiber contracts both in metropolitan areas and over long distances as part of development of a global backbone network." - Google job posting.
Google were keeping quiet and declining to comment on the above job posting, but it's got people talking about the possibility of a future Dark fiber Google network. However, this is purely speculation at this time.
If Google were to build its own global or national fiber network, the project would likely cost billions of dollars and take years to implement, an investment that would be hard to justify based on the networking needs of most companies.
Dark fiber does however remain a topic of increasing interest among the tech community, with private companies, universities and medical facilities all interested in what it could provide.