Rainmeter eats up a lot of CPU power though once you have several widgets open. I have been using rainmeter for a while, until I noticed that games ran a lot faster if I end Rainmeter first. Right now, even with the animated background and everything, it barely comes up to 2% CPU.
... Ok, now I have a boner for your shell. Minimalistic, stylish and saving ressources. As soon as you're done with it, I'm going to jizz my pants, that's for sure.
One last question, though... Ok, make that two: Are custom wallpapers still possible or is this mint green color oligatory? And: How does one get to programs, will there be some kind of dock or some alternation of the basic Windows start menu?