Got an application that won't play nice in Windows 7 or Vista, but works fine in XP or an even earlier version of Windows, like Me? Just grab an old Windows CD and install it within a virtual machine (VM). Then install your app.
VMware Player features Unity mode, which allows applications running in the virtual machine to appear as if they're running natively on the host computer. They have their own taskbar buttons and their own program windows, making for a seamless experience. For this to work, however, you'll need to install the VMware Tools program on the virtualized operating system. You're usually prompted to do this after installation of the OS has finished.
2. Access Virus-Infected Data
Ever been sent a file that your antivirus program has flagged, but which contains important data you just have to view? Most virtualization software includes snapshot functionality, which means you can create a "saved state" of the virtual OS and its entire hard disk. It's a little like travelling back in time.
You could create a snapshot in the virtual machine, open the infected file within the VM to access the data and, if the virus causes chaos, simply click to restore the VM snapshot. Hey presto--a clean virtualized computer.
3. Browse in Complete Safely
Why not install Windows on VMware Player, then install Firefox, and run it in Unity mode so it appears to run natively on the host computer?
Essentially Firefox will be running in what's known as a sandbox, meaning that should it (or one of its plugins) get hacked while you're online, there'll be no absolutely no risk to your actual operating system. You could create a snapshot once everything's been configured in the virtual machine in order to get things back up and running quickly, should anything go wrong.
4. Test Software, Upgrades, or New Configurations
The virus testing technique above isn't limited to malware. You could use your virtual computer to test new software, updates, or even new configurations of software before you roll them out for real on your main OS.