Sauron does his best impression of Galadriel when she gets too excited. (ie. Mirror of Galadriel from movie.)
OR
This is Sauron's twin. Sauron's the bad one, in case you didn't know.  
 
OR
Sauron has some major buck teeth.
OR
Sauron: "Oh, look, a lever! I wonder what it does?" *pulls lever* *gets electrocuted*
OR
101 Ways To Defeat a Dark Lord
#37- attach him to an arc welder.