Ctrl+Shift+Esc -> Task Manager (Ctrl+Alt+Del -> Tasks Screen)
Ctrl+Shift+Enter -> Run an executable with elevated privileges
Windows logo key+1-0 -> Launch the shortcuts on the Quick Launch toolbar
Windows logo key+T -> Cycle through programs on the taskbar
Windows logo key+Tab -> Cycle through programs on the taskbar by using Flip 3-D
Ctrl+Windows logo key+Tab -> Use the arrow keys to cycle through programs on the taskbar by using Flip 3-D
Windows logo key+Spacebar -> Bring all gadgets to the front and select Windows Sidebar
Windows logo key+G -> Cycle through Sidebar gadgets
Windows logo key+X -> Open Windows Mobility Center
Open a folder and press & release Alt -> Show Menu Bar (also works in Internet Explorer)