i know most of them though thanks...
a little add up for win7 users -
windows + E = Opens explorer
windows + D = Minimize ongoing programs and take you on desktop
windows + Space Bar = Transparent window that shows desktop
Alt + P = Opens a preview pane while you're browsing through pictures
windows + down = minimizes the current window
windows + R = run
and there are many.. these are a few that i commonly use..