Here are some useful shortcut keys for Windows 7 users.
Windows key + Up Arrow = Active window will be maximized
Windows key + Down Arrow = Active window will be minimized
Windows key + Left Arrow = Active window will be moved to the left
Windows key + Right Arrow = Active window will be moved to the right
Windows key + Home Key = All windows will be minimized. If already minimized they will be opened.
Windows key + T = The first application in task bar will be given focus. If you press T continuously the focus will be switched to other applications in that order.
Windows key + Space bar = If you keep pressed, Windows Startup will be shown.
Windows key +  1-9 any number key = The respective application in the task bar will be given focus.
Windows key +  Plus key = Window will be zoomed in
Windows key + Minus key = Window will be zoomed out.