Remember when Apple first started selling Macs that ran on Intel processors? Some Mac users felt that Steve Jobs would never allow Windows to run on a Mac. Others, myself included, felt that he would do whatever made the best business sense. Four months later, he did exactly that, by introducing the public beta of Boot Camp, software that enables Mac users with a valid Windows installation disk to install Windows and boot into either Windows or Mac OS X.

Boot camp was followed by Parallels, virtualization software that enables Mac users to run Windows inside a Mac window, so that the operating systems can be switched back and forth without rebooting. But both pieces of software require that you own a Windows installation disk, and both pieces of software carry with them whatever security risks are inherent to running Windows. This is where CodeWeavers’ (www.codeweavers.com) CrossOver Mac enters into the picture.

This is the most unique product I’ve found displayed at Macworld 2008. When I asked CodeWeavers’ CEO Jeremy White to compare CrossOver Mac to Boot Camp and Parallels, he told me “CrossOver Mac is a completely different approach than either of those products; CrossOver is a tool that allows Windows applications to run on Mac OS X as though they were native applications. You do not install or run the Windows Operating system itself in any way.”

I then asked about performance in graphics intensive programs, such as games and 3D rendering applications. Jeremy answered ”The applications integrate natively into the Mac environment (as much as a Windows application can), and run at essentially native speeds (which is obviously particularly critical for games). With CrossOver Mac, applications consume only the amount of RAM they would when run on Windows, take only the amount of disk space they use on Windows, and so on.”

That sounds impressive. The CrossOver Mac software, which is also available as CrossOver Linux (for Linux users that want to run Windows programs without installing Windows), is based on the Wine (www.WineHQ.org) open source implementation of the Windows API. To that end, CodeWeavers is the largest corporate sponsor of the Wine Project. In true open source style, an honest evaluation of the differences between the open source Wine and the commercial (but still very affordable) CrossOver Mac is available on the CodeWeavers website (http://www.codeweavers.com/products/differences/).

CrossOver Mac normally sells for $60, and is on sale during Macworld 2008 week (through Friday night, January 18th), for $40. A free trial version with a 30 day tryout period is available.