"9. Velociraptor's main weapons were its single, oversized hind claws.

Although its sharp teeth were certainly unpleasant, the primary weapons in Velociraptor's arsenal were the curved, three-inch-long claws on its hind feet, which it used to slash and jab at prey. It's possible that this raptor stabbed its prey in sudden, surprise attacks, then withdrew to a safe distance as its victim bled to death."

http://dinosaurs.about.com/od/dinosaurbasics/a/velofacts.htm