Several years ago I figured out how to convert the Virtual PC images windows used to provide for Windows testing to VirtualBox format, that would run on the Mac. It was a long process but was the only way to legally(ish) test Windows for free on your Mac.
This year Microsoft lauched modern.ie, where they providing Windows on free disk images compatible on Mac and Linux!
Pro Tip: Accessing localhost
Another improvement over the last couple years is how you can access servers running on the host system (i.e. your Mac) from the virtual version of Windows running in VirtualBox. Now it’s as simple as modifying your Windows hosts file.
When the VirtualBox Guest Additions are installed (Devices > Install Guest Additions) you can access your Mac via the IP address:
To give it a name, like localhost, edit
C:\Windows\System32\drivers\etc\hosts and add the following line to the end of the file:
Now open IE (close it first, if it was already running) and enter localhost in your URL bar. You should now be accessing the web server running on your host system.