At the high end, IT shops are replacing a bunch of blade servers with one big machine running EXSi (a bare-metal VMWare server) hosting a bunch of virtual machines. There are some big benefits to this, not the least of which is reduced floor space and power requirements.

But for individual computer users, virtualization can also be useful. One area where the use of virtual machines has taken off is giving Macintosh users the ability to run Windows software on their machines without dual-booting -- and that's what we're going to discuss in this article.

VMWare is one of the big names in virtual machine software. Here at Computing Unplugged we use a variety of VMWare products constantly. We often use a VMWare workstation and server to run test instances of Windows or Linux on our Windows machine.

A week ago, for example, I set up a test instance of the BSD-based FreeNAS server on my laptop, assigned it a set of virtual hard disk volumes, and proceded to pound on it to learn its performance parameters.

The Mac tax
For Windows users, most of the VMWare products are free to download and use. For Mac users, not so much. If you're a Mac user, you can buy VMWare Fusion for $89 directly from VMWare. Weirdly enough, we were provided our review copy of VMWare Fusion 2.0 by SmithMicro Software (the guys who publish StuffIt), but their Web site shows nothing about VMWare Fusion -- so we recommend you get the product directly from VMWare.com.

Once you get past the idea that your machine is quite adeptly running other machines inside it (and no, I have yet to get over this, and I use the Windows product every day), you'll realize that the various VMWare implementations are universally quite solid.

I wasn't happy when VMWare went from version 1.x to version 2.x and did away with a regular application for management and instead insisted the virtual machines be run from within a browser interface (I didn't like having to have browser Windows dedicated to the virtual machine), but it's certainly workable.

Tuned for the Mac
VMWare Fusion is particularly tuned to the Mac. One of the more interesting features is one where Windows applications now appear to exist side-by-side with Mac applications, as if they were directly installed on the Mac. You can move windows, and cut and paste between Mac and PC windows without much thought to the magic of the whole process.

Overall, we were very impressed and if you only use a Mac, you probably should buy this product. If you're primarily Windows users, like we are, you might be better off just downloading VMWare for the PC and not paying the Mac tax.