LinuxMInt in several different configurations. Home net has 8 machines, only 2 of which have any version of Windows, 1 w/ Vista and the other with Win7. They exist only for testing purposes when designing sites, and once a year during tax season.
I am using both windows XP and Windows 8. I've been using Windows XP since I first touched and used a computer desktop.
But I now have a laptop with Windows 8.1 OS. So, I use both alternately. And it's cool to use the latest.