Intel Mac users will be able to run Windows applications, including some games, without having to run the operation system, according to software company CodeWeavers, which has produced a $60 crossover programme.

A number of software companies already offer a similar service, but Boot Camp makes users reboot their Macs and run Windows, and Parallels Desktop is a virtualisation programme that runs Windows on a Mac OS X but within a separate window.

CodeWeavers' CrossOver Mac however doesn't use this "box within a box approach," said chief operating officer Jon Parshall. "What you see running is an application sitting in your Dock or your Applications folder," Parshall said.

Both Boot Camp and Parallels Desktop work because the new Macs use Intel processors, and CrossOver Mac employs the same basic principle.

Although Boot Camp is free and Parallels Desktop is reasonably priced, both software applications require an expensive copy of Windows in order to work, but not CrossOver Mac, the company claims. It works without having Windows installed altogether, thanks to the underlying code that powers the software.

CrossOver Mac is based on the same core technology that powers CodeWeavers' Linux-based offering: an open-source project called WINE, a compatibility layer that provides alternate implementations of the code used by Windows applications.

CodeWeavers used publicly available versions of WINE to develop CrossOver, and will provide its code changes back to the WINE project, according to Parshall.

Applications running on CrossOver Mac will offer performance comparable to apps running natively on Windows, according to Parshall, with all the same capabilities and functionality as they would if you were running the Microsoft OS.

CrossOver currently works with Microsoft Office applications Access, Project, Vision, Lotus Notes, Quicken, FrameMaker and assorted others.

The company said it hopes "to offer support for a limited number of games" but hasn't yet determined the final mix of supported applications. Parshall told Macworld that the popular shooter Half-Life 2 is on the list.

Another benefit of CrossOver Mac's approach to running Windows software is that it's much less susceptible to infection by Windows-based viruses or malware than a true Windows-based solution, according to Parshall. "A virus needs to affect the guts of Windows," he explained. "Theoretically, if you were really, really good you might be able to get your virus to run under WINE, but we've yet to hear about anyone who has, even in the laboratory."

CodeWeavers plans to release CrossOver Mac in July or August. It will cost $59.95 for a single-user licence.