A VERY simple distro of Linux, perhaps? I don't know for sure. I just said that 'cause Clevin is usually posting desktop pics from Linux. Either way, it looks simple to use, though not that appealing to look at, IMO.
I guess it's running on that EEE laptop.
Isn't it the desktop from the Asus EEE PC?
[EDIT: Rats! Beaten to it]
yepper...
its so hard to find good wallpapers, my MB's wallpapers (4, with virtual desktops' overlay function) haven't been changed for months.