Tabs and Windows

Function	Shortcut
Change Pane size	⌘ + Option + Arrow Key
Splitting
Split Window Vertically	⌘ + D
Split Window Horizontally	⌘ + Shift + D
Moving
Move a pane with the mouse	⌘ + Option + Shift and then drag the pane from anywhere

Shell Key Combos

Function	Shortcut	Use
Delete to start of line	Ctrl + U	Use this to start over typing
Delete previous word	Ctrl + W

Moving

Function	Shortcut
Move to the start of line	Ctrl + A
Move to the end of line	Ctrl + E
Move forward a word	Option + Right Arrow
Move backward a word	Option + Left Arrow
Cursor Jump with Mouse	Option + Left Click

Search the Command History

Function	Shortcut
Search as you type	Ctrl + R and type the search term; Repeat Ctrl + R to loop through result
Search the last remembered search term	Ctrl + R twice
End the search at current history entry	Ctrl + Y
Cancel the search and restore original line	Ctrl + G

Other

Function	Shortcut
Clear the screen/pane (when Ctrl + L won't work)	⌘ + K (I use this all the time)
Broadcast command to all panes in window	⌘ + Option + I (again to toggle)
Find Cursor	⌘ + /