I don't know if this would work, or even how useful it would be but see what you think anyway. If i were to make a main site that i wanted to be an authority. would it work if i made up a niche lets say focused on a made up sport called "walttball" where there are a total of 5 results in google. then create a few articles / backlinks etc. maybe even a couple more sites linking to the main site to add credibility. do you think this would quickly achieve authority site status and would it be useful to, over time change the focus of the site and migrate it to something useful or just use it to promote other sites i might have. Its half an idea at the moment , think it could be useful ?