The big gorilla of virtualization. VMWare has not been napping while other vendors and technologies are trying to push ahead. VMWare uses a different approach to virtualization than Xen. VMWare is an emulator; it creates a virtualized hardware environment for the guest operating systems. Emulation is resource-intensive, but VMWare claims equal or superior performance to Xen. You can bet your last glass of microbrew that they are busily at work taking advantage of Intel's and AMD's hardware support for virtualization for even better performance.

VMWare's bigtime enterprise editions are predictably spendy, but you can download VMware Player and VMware Server for free. Then presumably get hooked, and start writing checks for the expensive stuff.

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