Trakr:
Trakr, seen here with Canadian Police officer James Symington, discovered the last survivor of the September 11 attacks at the World Trade Center.
Genelle Guzman-McMillian was making her way down the stairs in the South Tower when the building collapsed around her. After being trapped for 27 hours beneath the concrete and rubble, Trakr alerted the firefighters to her whereabouts.
Before Trakr died in April 2009, his DNA was entered into a cloning contest by Symington and was later chosen for use. In June of that year, five cloned Trakrs were born.