Some Photoshop Shortcuts.

1-0: Master Opacity Change (1-Clear 9/0-Solid).

Delete: Deletes what is selected.

Tab: Hides photoshop tools.

Q: Quick Mask.

W: Quick Selection Tool
Magic Wand Tool.

E: Eraser
Background Eraser
Magic Eraser.

R: Rotate View Tool.

T: Horizontal Type Tool
Vertical Type Tool
Horizontal Type Mask Tool
Vertical Type Mask Tool.

Y:History Brush Tool
Art History Brush Tool.

U: Rectangle Tool
Rounded Rectangle Tool
Ellipse Tool
Line Tool
Custom Shape Tool.

I: Eyedropper
Colour Sampler
Ruler Tool
Note Tool
Count Tool.

O: Dodge Tool
Burn Tool
Sponge Tool.

P: Pen Tool
Free Form Pen Tool.

A: Path Selection Tool
Direct Selection Tool.

S: Clone Stamp Tool
Pattern Stamp Tool.

F: Normal Space
Fill Gap Space
Full Screen.
(You'll Understand If you press it...).

G: Gradient Tool
Paint Bucket Tool.

H: Hand Tool.

J: Spot Healing Brush Tool
Healing Brush Tool
Patch Tool
Red Eye Tool.

K: 3D Object Rotate Tool
3D Object Roll Tool
3D Object Pan Tool
3D Object Slide Tool
3D Object Scale Tool.

L: Lasso Tool
Polygonal Lasso Tool
Magnetic Lasso Tool.

Z: Zoom In (Press option/alt- changes zoom [in/out]).

X: Swaps the Colour Boxes
Black and White Boxes
(Again, you'll have to click it to understand)

C: Crop Tool
Slice Tool
Slice Select Tool.

V: Move arrow (Don't know what it's called... it moves what you select)

B: Brush Tool
Pencil Tool
Colour Replacement Tool
Mixer Brush Tool.

N: 3D Rotate Camera Tool
3D Roll Camera Tool
3D Pan Camera Tool
3D Walk Camera Tool
3D Zoom Camera Tool.

M: Rectangle Marquee Tool
Elliptical Marquee Tool
Single Row Marquee Tool
Single Column Marquee Tool