As sales of Apple's Macs expand, so does the number of ways to run Windows software on Apple hardware.

Two new methods offer Mac users access to Windows applications, but unlike Boot Camp or Parallels, they don't require running Windows itself or the Windows desktop.

CrossOver from CodeWeavers is a commercial product based on the open-source Wine program. The company has a Linux version and plans to release a Mac version in August.

True North Technology's Northstar is a Web-based service that also employs X11 and Java. CrossOver runs only on Intel-powered Macs; Northstar works with PowerPC-based as well as Intel-based Macs.

Both provide Windows applications in their own windows on the Mac, giving users access to Windows applications and the Mac OS X software at the same time. Neither, however, is a virtual machine product.

Windows programs without Windows may be exactly what most Mac users want. Users can run Outlook instead of the less-capable Entourage, or run Internet Explorer when Safari isn't supported.

And with the Window-less approach, the Mac isn't saddled with supporting the overhead of two operating systems. In addition, users don't have to navigate through unfamiliar Windows GUI elements to get to applications and files.

There is no Start menu or Windows task bar. With Northstar, users choose applications from a window. CrossOver has a Programs menu in the Mac OS X menu bar that lists Windows applications. Windows programs can minimize in the Mac OS X Dock, so a task bar isn't needed.

Unlike a virtualization environment, CrossOver stores users' files created by Windows applications in Mac folders, not in a virtual disk image or a separate partition. Windows applications see the Mac's home folder as a Y drive.

CrossOver may also be the least expensive way to run Windows programs on a Mac. Although Boot Camp is free, it requires the user to own a licensed copy of Windows XP; CrossOver does not.

CodeWeavers CEO Jeremy White said that CrossOver will not run every Windows application, but it will be optimized for a set of tested applications, including Outlook, Project and Visio.

"This is just for the 1.0 version," said White. "We'll be adding more [optimized applications] in future versions."

He also said that CrossOver should also run some Windows applications that haven't been optimized.

Because CrossOver has support for the Intel Mac's native graphic hardware, it will be able to run PC games, according to White. Boot Camp can run PC games, but Parallels Desktop cannot.

White said that CrossOver uses no Microsoft code. Neither does the open-source Wine. There is a free, open-source port of Wine for Mac OS X called DarWine, but CrossOver is far ahead in terms of stability, compatibility and integration with the Mac interface.

CrossOver is not based on DarWine, but is a direct descendent of Wine for x86. White said that this was because CodeWeavers engineers are also Wine developers.

"We're the leading sponsor of the Wine project," said White.

While CrossOver runs Windows applications in Mac OS X windows, DarWine runs them in an X11 window, requiring the Mac to have Apple's X11 for Mac OS X installed.

Like DarWine, Northstar puts Windows applications in an X11 window on the Mac. Users log on to the Northstar service with a Web browser. Northstar then sends down a Java tuner applet that feeds X11 packets that represent the display.

But Northstar strays even further from the virtual machine model and may be an approach that will be more difficult for users to grasp.

For starters, Northstar users don't need to own their own Windows applications. True North will license applications on an annual basis, or on a monthly basis if the user only needs to use the application for a short time.

The company offers different pricing packages for sets of software, and offers business and enterprise subscriptions. True North will keep Windows application up-to-date and apply the latest service packs.

For a fee, True North will let customers upload their own Windows software to Northstar or mail the company the disc media. The service makes installed software available to the user through an interface element called the Northstar Desktop.

But Northstar isn't a hosting service in the sense that it doesn't dedicate hardware and software to a customer. The service uses server farms that provide all the hardware that it takes to deliver the applications for as many users as the customer adds to a subscription.

Northstar is also not an application server, like a Citrix server or Microsoft Terminal Server, according to True North CEO Doug Nassaur, who said that Northstar has a 5-to-1 performance advantage over Citrix.

Instead, Northstar provides software on-demand, like a video-on-demand service using a proprietary switching network.

"With software as a service, we can look at how much demand we have and reapportion it as necessary," said Nassaur.

True North started R&D in 2001 and went live last year.

"We spend 4 years [and] millions of dollars on developing our own switch technology," said Nassaur. "We had to build a telco-quality network. We had to automate how users can get to the applications."

Nassaur said that at some point in the future, the Northstar service will offer software in increments much smaller than a month. "If you only use an application 40 minutes per year, you'll only pay for what you use," said Nassaur. He did not indicate when the fractional pricing would be available.

Unlike applications servers such as Citrix and RPD, all files and settings are saved on the server by default. This has advantages for users.

"[Northstar is] session-based, not computer-based, so if the user's computer crashes, he can pick up right where he left off," said Nassaur. "You can also move to another Mac or PC, in the same office or in another city. We want to license software to people, not computers."

Another concept that takes some getting used to is Northstar's offerings of enterprise groupware and services, including domain controlling, Active Directory and Exchange server.

The transactions between clients, and between clients and servers all occur on True North's server farms, not locally, and not over the Internet.

"In our world, the client and the server are both sitting within Northstar," said Nassaur. "What we send to the user is an image of the result."

Mac users and Windows users are treated equally, and both types of users have access to everything in Northstar with a single sign-on using Kerberos.

True North hopes that the enterprise subscriptions to Northstar will be attractive to small and midsize business who don't want their own servers or IT departments.

True North will eventually offer Mac OS X applications to other operating systems. Nassaur said that the company is working on Linux support in Northstar that will allow Linux users to run Macintosh as well as Windows applications on Linux.

"Ultimately, what we're about is running any app on any platform anywhere," he said.

Check out eWEEK.com's Macintosh Center for the latest news, reviews and analysis on Apple in the enterprise.

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