We can argue until we're blue in the face that the Mac does things better, or that you can achieve the same things under Mac OS X as under Windows, just in a slightly different way, but the reality is that the ability to run Windows is sufficiently desirable, and many Mac users have a cheap Dell box lurking under a table somewhere.
That all changed in January 2006 with the introduction of Intel-powered Macs. This move meant that, at a hardware level, Macs were essentially identical to other PCs in the market, and it prompted Apple to develop its Boot Camp system that allowed you to partition off a chunk of your Mac's hard disk, onto which you could install Windows.
One computer could now run both systems, though you had to shut down the Mac side completely to reboot into Windows, and vice versa.
Parallels changed that, too. Now, once you'd bought a copy of Windows, you could run it alongside Mac OS X, in a window that behaved no differently to any other window in OS X.
Switching between the two involved sweeping your mouse from one window to another, and because Parallels Desktop is a virtualised system, rather than an emulated one - it's able to directly access the Mac's processor, rather than having its instructions translated from one architecture to another, as with Virtual PC - there was very little performance hit.
Parallels Desktop 3.0 is the new release of the virtualisation system, and it adds three major new features. The most exciting is support for 3D, though that should read 'some support for 3D'. It brings DirectX 8.1 to its virtual PCs to give some support for 3D gaming and CAD applications.
Performance is reasonable, particularly if you cut the company slack for achieving so much in a '1.0' release of this technology, but there's a long way to go.
The existing implementation needs tuning, as even with some older games, settings must be turned down if frame rates and audio sync are to be maintained, and there are hardware limitations; while processor virtualisation is made possible at the hardware level with Intel VT-x, graphics hardware is still, in effect, emulated.
There's no support for DirectX 9 - the current standard that also powers the translucent effects in Vista - nor the emergent DirectX 10, and hardcore gamers will still be better served investing in dedicated hardware, but this is an excellent first release. OpenGL is also supported.
SmartSelect is less sexy, but adds more to the app's appeal. The idea is that you can right-click on a document, whether it's in the host (Mac) OS or the guest (usually Windows) OS, and from the Open with sub-menu pick an app from either environment.
You can also set global preferences so that, for example, double-clicking a .psd document in a Windows virtual PC prompts it to open in Photoshop on your Mac.
We noticed one glitch: attempting to open a document stored on your Mac, accessed via the .psf system from the Windows environment, opened a new, blank document in the host app, rather than opening the document itself. We expect to see this patched soon.
When viruses attack
Finally, the Snapshot system allows you to capture your virtual machines' state so you can roll back to earlier versions should a virus take hold; this works well, but it's worth manually copying off the virtual hard disk document to an external volume for backup.
Parallels Desktop 3.0 now allows you to specify your Boot Camp partition as the boot volume if Vista is installed there - previously only XP was supported - though we did run into some problems; proceed with caution.
The 3D provision seems a little meagre, and Parallels hasn't yet worked out how to show the virtual machines more than one processor core from the host Mac - something the competitor VMware Fusion does, though it's still in beta - but the system still seems like magic, and for those of us who must suffer the ignominy of Windows, it remains one of the best-value pieces of software around.