One of the nice things about virtualization is that the concept of appliances came into being, in the same way that a refrigerator is a single purpose device to keep foods cold. And a microwave gets things hot, fast, virtual server appliance are single purpose piece of software that can be installed on a virtual host, aka server with VMware, XenServer or Hyper-V with very little effort.
You usually pick one from a list, click on it and it will download to your virtual server; it installs itself and one last click to start the newly installed server. What could have taken days to manually install and configure has been reduced to ten minutes! And if you don’t like the newly installed appliance, you can delete it with a few more clicks. Or you can just install a few with similar designs and run them one at a time to find the one you like.
Several specialty software vendors, notably Untangle and Astaro both produce appliances, I think for specifically VMware that provide an instant deployment within 30 minutes… remarkable. Take a look and think of the possibilities. They aren’t free and depend on a subscription model to support their products.
http://wiki.untangle.com/index.php/Untangle_Virtual_Appliance_on_VMware
http://www.astaro.com/products/astaro-security-gateway-software-appliance
