I visited your website and then your business that deals with developing and hosting RonR. Very impressive! Thanks for responding to my question.
My basic plan is to develop 'clusters' of websites. As a fictious example lets take a website for everyone that has birthdays in the month of March. There is a main website called www.MarchBirthdays.com but then also 30 others such as www.March_01_Birthday.com and so on.
My objective is to run 30 websites that use the same Ruby logic, but when a user accesses www.March_01_Birthday.com, they see a 'common RonR application' running, but the forums, wiki, Digg, articles, books, etc. gain their data from data elements in the database that are sub-tables of the (I call it project) highest level table. Now, If I haven't confused you too much here's how it plays out.
There is a main RonR program sitting in the www.MarchBirthdays.com/public folder that receives requests through the Apache VHost from user either the traditional request of "http:\\www.March_01_Birthday.com" or for those that are active in their particular website who've saved the link "Project\controller\action\keyvalue". This program is like a 'quarterback' as he reads the incoming requests, and calls the plays. The 'project' is an integer key that's part of a record that holds fields like 'program', 'program name', 'program location'. In the two types of http requests shown above, it deciphers the project integer and then calls the application program through the project_id. The project_id record then provides the logic of what program - database combo to call.
The long and short of this is that my "Hope" is to use a strategy like this INSTEAD of 30+ distinct domains, without having to write and install many (almost) identical (save for data) applications on a server.