Image adjustment shortcuts
There are quite a few shortcuts you can use to bring up image adjustments, rather than fishing around in the Image>Adjustments menu. However I generally use adjustment layers that allow you to combine image adjustments in a non-destructive way, rather than these permanent adjustments, but they are sometimes useful to remember!
I have put the most useful ones at the top in bold, the rest you should learn at you leisure fellow Photoshop Ninjas!
Command+L = Levels
Command+M = Curves
Command+B = Colour Balance
Command+U = Hue and Saturation
Shift+Command+U = Desaturate
Command+I = Invert
Shift+Command+L = Auto Levels
Option+Shift+Command+L = Auto Contrast
Shift+Command+B = Auto Colour