Metro reminds me of the Acer Computer Explorer (I think that was the name, I was 11 at the time) that was installed on my very first computer (windows 95).
The computer booted up to a home screen with icons for all of your programs, and you had to click exit to desktop to get into windows.
Come to think of it, the start screen isn't too far off from At Ease either. I remember all the Macs in school ran locked down copies to keep the students from messing with the computers and make it easier to find programs for the little kids.
The computer booted up to a home screen with icons for all of your programs, and you had to click exit to desktop to get into windows.