The Cosmic Dancer who dances Creation into and out of existence. "The Lord of the Dance." One of the many incarnations/aspects of the Hindu god Shiva.
Most famous story: The sages living in the southern forest regions of India had attained great powers through meditation and ritual, but had grown arrogant and no longer praised the gods. So Shiva appeared in the forest as an ithyphallic mendicant named Bhikshatana and wandered about their villages, begging. Bhikshatana's . . . excitement . . . caused many of the sages' wives and daughters to become enamored with him, so the sages decided to use their powers to destroy this out-of-line beggar. First they summoned a fierce tiger made of fire, whose pelt Bhikshatana made into a loincloth. Next they sent a horde of poisonous snakes, which Bhikshatana hung about himself as jewelery. Then came a mad dwarf, which Bhikshatana stomped upon. (The twisted thing underneath Nataraja's feet in the depiction above is this wild dwarf.) A third eye formed in the beggar's forehead, two extra arms grew out from his torso, fire blazed into life in his upper left hand—and Shiva-as-Nataraja danced the Ananda Tanvara, which caused the monks to realize exactly who he was and recognize the error of their worship-neglecting ways.
The first depictions of Shiva as the Lord of the Dance appear in bronzes crafted in 10th - 12th century India. Nataraja is nowadays more a symbol than anything else, although he is to this day revered in India and elsewhere. As Ananda Coomaraswamy says in his essay "The Dance of Siva," "Whatever the origins of Siva's dance, it became in time the clearest image of the activity of God which any art or religion can boast of." To this day the Nataraja symbol be found in both Eastern and Western culture.
Powers and Abilities: Beyond comprehension. Not many mythological beings have the power of creation and destruction literally resting in the palm of their hand. Mythological beings gain their powers from ken, or "knowledge-of". The more well-known a mytho is in the great Mind of humankind, the more ken they have to utilize. Shiva-as-Nataraja may be to many just a symbol, but sometimes symbols have frightening power. Again, Coomaraswamy, "A great motif in religion or art, any great symbol, becomes all things to all men." As to whether or not Nataraja dancing the Samhara portion of his Ananda Tanvara could actually destroy the universe . . . well, we all know what happened in Eden last summer.
UPDATE - 5/9/12: This agent was on the scene for that scene, and that that ball of fire gripped in Nataraja's upper left hand is hot hot hot!