Voyager 1, now 13 billion miles (21 billion km) from Earth. First venture into interstellar space for the human species, lets hope whoever finds it are friendly.
http://news.yahoo.com/scientists-confirm-voyager-1-probe-interstellar-space-204809737.html
http://news.yahoo.com/scientists-confirm-voyager-1-probe-interstellar-space-204809737.html