During the Italian Free Software Conference in Trento, I attended an amazing presentation on virtual components.
Renzo Davoli, professor at Bologna University and hacker, has stretched the concept of virtualization to new limits. Virtual Square is a project aiming at developing more dynamic implementations of virtual entities, which eventually get separated from the concept of operating system and root privileges.
The coolest aspect of all this project is the virtualization of single elements like a disk drive, a net port, a file system, without root privileges, and with no impact on other users.
Virtualizing single elements makes life easier for demanding users, and more quite for their neighbors, who won't be affected by massive reduction of overall resources as it happen with normal virtualization of operating systems.
Think of the applications: for example, it would be easier to establish dedicated quotas for database and web server users, with better security and easier maintenance and without creating new OS users. MySQL, with its limited interface for user resources, would surely benefit from this system. There is a lot of potential in this idea. Let's hope it is pushed a bit farther than the academic circles.