Duals

Most Duals will probably be opposites(eg. antonyms) but you shouldn't limit yourself to just them.

Salt	Pepper
Odd	Even
Up	Down
Left	Right
Arrive	Depart
Big	Small
Tweedledum	Tweedledee	Through the Looking-Glass and what Alice Found There
Statler	Waldorf	Muppet Show
Positive	Negative
Day	Night
Happy	Sad
In	Out
Grin	Grim	:)  :(