Now I can see this becoming very useful in many different production environments, not just those hosting websites...

This article describes how to combine the built-in Integrated Load Balancer (ILB) with Oracle Solaris Zones and the new network virtualization capabilities of Oracle Solaris 11 to set up a virtual server on a single system. This article starts with a brief overview of ILB and follows with an example of setting up a virtual Apache Tomcat server instance.  You will need a basic knowledge of Oracle Solaris Zones and networking administration.
How to Set Up a Load Balanced Application Across Two Zones