Blender Shortcut Keys

Viewport
Scene Rotation = Middle Mouse Button
Scene Pan= Middle Mouse + Shift
Scene Zoom = Middle Mouse + Ctrl

                                                            View Change
                                                            Front = Numpad 1
                                                            Side = Numpad 3
                                                            Top = Numpad 7
                                                            Ortho/Perspective = Numpad 5

Object Mode = Tab
Transform = G
Rotation = R
Scale = S
Lock to Axis = X, or Y, or Z
Add Mesh (& others) = Shift + A
Duplicate = Shift + D
Combine Mesh = Ctrl + J

Edit mode = Tab
Transform = G
Rotation = R
Scale = S
Lock to Axis = X, or Y, or Z
Selection Type (Vertex, Edge, Face) = Alt + Tab

Add Mesh = Shift + A
Create Edge Loop = Ctrl + R
Select Edge Loop = Alt + Left Click on Edge
Edge Slide = Double Tap G
Duplicate = Shift + D
Delete/Dissolve Menu = X
Box Select = B
Extrude = E
Polygon Cut (Knife) = K
Separate Mesh = P

Specials menu = W
Merge = Alt + M
Bevel = Ctrl + B
Inset = I
Fill Face = F

Hide = H
Un-hide = Alt + H
Edges Menu = Ctrl + E
Unwrap = U

Modifiers & Shortcuts
Skin Modifier (While in Edit Mode)
Create Vertices and Edges = Ctrl+Right-Click
Add/Subtract Mesh Volume = Ctrl+A