After enjoying "The Hobbit" I started thinking of the Jewish tradition of dragons. In the coming week, I'm hoping to examine some of the lesser known Jewish sources dealing with dragons, especially from the Apocrypha. I'm no Natan Slifkin, and my knowledge of these issues is very casual, and meant mostly as "Whoa, dragons, cool".
That the dragon was a potent symbol for Jews is undeniable. Perhaps the clearest sign that dragon were a widely used symbol comes from the apocryphal additions to the book of Esther. The additions to Esther begin with Moredchai dreaming a puzzling dream, foretelling the story:
 In the second year of the reign of Artaxerxes the Great, on the first day of Nisan, Mordecai the son of Jair, son of Shimei, son of Kish, of the tribe of Benjamin, had a dream.
 He was a Jew, dwelling in the city of Susa, a great man, serving in the court of the king.
 He was one of the captives whom Nebuchadnezzar king of Babylon had brought from Jerusalem with Jeconiah king of Judea. And this was his dream:
 Behold, noise and confusion, thunders and earthquake, tumult upon the earth!
 And behold, two great dragons came forward, both ready to fight, and they roared terribly.
 And at their roaring every nation prepared for war, to fight against the nation of the righteous.
 And behold, a day of darkness and gloom, tribulation and distress, affliction and great tumult upon the earth!
 And the whole righteous nation was troubled; they feared the evils that threatened them, and were ready to perish.
 Then they cried to God; and from their cry, as though from a tiny spring, there came a great river, with abundant water;
 light came, and the sun rose, and the lowly were exalted and consumed those held in honor.
Two dragons are fighting, while the world is brought into a great distress. We are not offered much of a description of the dragons, so it is impossible to understand whether "dragon" = flying lizard spewing fire, or just a generic word for monster. The dream itself is solved in a later chapter:
And Mordecai said, "These things have come from God.
 For I remember the dream that I had concerning these matters, and none of them has failed to be fulfilled.
 The tiny spring which became a river, and there was light and the sun and abundant water -- the river is Esther, whom the king married and made queen.
 The two dragons are Haman and myself.
 The nations are those that gathered to destroy the name of the Jews.
The author clearly saw dragons as creatures of great power, though they don't really do much in this narrative. The dream as an addition to the book of Esther, seems to be intent on adding "God's" influence into the biblical narrative.
Hopefully, some future dragons will be slightly more active.