Reading this Open Source and business article, a thought pops into my mind: the micro/small businesses described by docwhat and the structure of the economy that would result from a proliferation of such businesses (as opposed to the monolithic business model that is currently in vogue) would be very similiar to a modern unix system, with many small individual (and separate) components working together to form a complete OS.
Perhaps this is the next step in changing current business practice. The first big change has been the shift in emphasis from selling software to selling service; the second may be one from servicing a single operating system to servicing an application across however many platforms it supports. On the other hand, the range of apps that *are* supported on several operating systems is naturally fairly small, given that many things are either tied to a specific OS (especially security things) or duplicate functionality of one OS in another (samba).