Ctrl + J (New Layer Via Copy) - Can be used to duplicate the active layer into a new layer.Using Ctrl + Click on a layer without a mask will select the non-transparent pixels in that layer.
Useful if you want to duplicate a mask or it’s inverse.
Ctrl + Alt + Shift + N (New Layer No Dialog) - Quickly insert a new empty layer on top of the active layer.Also use Ctrl + Alt + Shift + S to bring up the save for web dialog. Ctrl + S (Save) - You should get in the habit of just hitting this combo on impulse about every 5 to 10 minutes.Ctrl + Alt + Z (Step Back) - Ctrl + Z is OK if you catch a mistake immediately after it happens, but this command will continue to march its way up the history tree.Alt + Mouse Scroll (Zoom In/Out) - Fastest way to zoom - scroll up to zoom in, and scroll down to zoom out.Ctrl + ‘+’/’-‘ (Zoom In/Out) - Quickly zoom in or out without changing your current tool.D (Default Colors) - Reset your foreground and background colors to black and white, respectively.X (Switch Colors) - Swap your foreground and background colors.Works great when used in conjunction with Tab to hide toolbars - maximum working space, no distractions.