I believe keyboard shortcuts improve my efficiency. The also make you look like a pro. Here are some of my favorites, which all work on Windows 7:
(Windows + E) - Opens a explorer window to get to your drives, folders and files.
(Windows + M) - Minimizes all open windows to the Task Bar
(Windows + Home) - Minimizes all open windows to the Task Bar, except the active window
(Windows + Arrow Up and Windows + Arrow Down) - Maximizes your active window and restores it to the previous size, respectively.
(Windows + Left Arrow and Windows + Right Arrow) - Windows + Left Arrow makes your active window fill half the screen. Windows + Left Arrow repeatedly will move it to the other side of your monitor or the other monitor and eventually restore it's original size. Windows + Arrow Right will simply restore it to it's previous position or size. This shortcut is handy for moving a window to your second monitor.
(Windows + + and Windows + -) - Activate the magnifier and zoom in or zoom out.
(CTRL + + and CTRL + -) - Zooms in or out on the text in page or doc.
I admit to really needing the last two. ;-)
Try these out. They may take a little practice and change of habit to work into your routine but they can save you time. Feel free to share your favorite keyboard shortcuts.