I love the Windows Key (WK). My two most used keyboard shortcuts are WK-E to bring up Explorer and WK-R to bring up the Run dialog box. WK-M is also a favorite, but I have this bound to a mouse-button so I only tend to use it while on other peoples computers.
I'm a little peeved about the Windows Key though, because there isn't as many shortcuts that utilise it as I'd like. Why is there no WK-N for notepad, and WK-C for the calculator, WK-I for a web browser or even WK-W for a word processor..? The other thing that annoys me, is that you can't specify the Windows Key for use in the shortcut key combination on your own shortcuts..
Don't forget the W-D combo which hides, and then reveals, all open windows!
Nice one. I use that all the time, but I have it bound to a mouse button..