The chupacabra (courtesy of Wikipedia) is a creature said to inhabit parts of the Americas. It is associated particularly with Puerto Rico (where it was first reported), Mexico, and the United States, especially in the latter's Latin American communities.
The name translates literally from Spanish as "goat-sucker". It comes from the creature's reported habit of attacking and drinking the blood of livestock. Physical descriptions of the creature vary. Sightings began in Puerto Rico in the early 1990s, and have since been reported as far north as the Carolinas, and as far south as Chile.
Though some argue that the chupacabras may be real creatures, mainstream scientists and experts generally contend that the chupacabra is a legendary creature, or a type of urban legend.
Here's a story from '04. A picture and another.