VMware Server is a robust yet easy to use product for users new to server virtualization technology. VMware Server enables companies to partition a physical server into multiple virtual machines, and to start experiencing the benefits of virtualization.

[ VMware Server ]

And it's free! So you install it, you love it, you need it, but the demands on your systems require more stability, better fault tolerance, next thing you know every solution is based on their ESX server and you don't know how you lived without it. Welcome to the future.