I think a super-simple personal content server is a great idea. I've heard about the entertaining time some people have had with respect to setting up personal content servers on their home LANs, and have stayed clear of them. Opera Unite has persuaded me to reexamine my thinking in this area.
As an internal personal/family LAN file/media server, it's great. Its lack of security makes it iffy for a company intranet, even behind a firewall. Stability needs improvement, too, though if you only plan to use it on an “on-demand” basis, it's less critical. Even if you implement my security setup recommendations, this is still trivial compared to, say, an Apache installation.
Password/cookie handling needs to be fixed. Also, there really needs to be a global top-level password option so a user accessing the main page can fill in a single password to access all services.
With the security fixed, this would make a nice low-traffic non-ecommerce webserver on a dedicated boxespecially with about half the performance of Apache, but with no elaborate setup.
I've seen speculation that Opera's major competitors might add this kind of functionality to conventional webservers. Mozilla/Firefox is the only one I think might actually do this. Microsoft and Google are sufficiently tied to the cloud business model, so I think it is extremely improbable that they will offer web browser functionality that's independent of their cloud-provided services.
Browsers and servers are sufficiently different, so I don't really see any synergy in combining the two. If Opera wants to distribute the server with the browser, it can make it a single-click download/install from the toolbar or something like that. And if it wants configuration to default through the Opera Unite site, it can have it copy information from the user ID information in the Opera browser in the setup process.