Here are some handy keyboard shortcuts for Windows Vista that Caley found earlier today.

Windows Key + Spacebar: Show Windows Sidebar
Windows Key + D: Show Desktop
Windows Key + Tab: Flip 3D Windows
Ctrl + Windows Key + Tab: Flip 3D which stays on desktop, you can then scroll with up, down, left and right keys
Windows Key + E: Opens Explorer window
Windows Key + R: Opens the Run dialogue box
Windows Key + T: Tabs between running applications on the taskbar
Windows Key + F: Opens the search window
Windows Key + G: Gives the sidebar the focus and when you press this key combination again it tabs between the gadgets on the sidebar
Windows Key + L: Locks the computer
Windows Key + U: Opens the Ease of Access Center
Windows Key + M: Minimizes all windows
Shift + Windows Key + M: Undo minimize windows
Windows Key + X: Opens the Windows Mobility center
Windows Key + Number: Press the Win key and then choose a number of the applications that are in the quick launch task bar. An example would be if second icon on the taskbar (starting from left) is IE, you would press Windows Key + 2 and it will launch IE.