If there's intelligent life within 100 light years of our planet, it's likely they've already gotten an earful (or antennae-ful, or whatever analogous organ-ful) of our radio and TV shows, which have been leaking into space since we first started broadcasting them. Scientists have also sent messages, images and even phonograph records into space in order to show E.T. that humanity isn't just about 'The Lone Ranger' and 'I Love Lucy.'
Who’s visiting who? This chart of solar system exploration shows every robotic space probe currently exploring (or about to explore) a major solar system object… except for the Earth and Sun of course, because there are way to many of those to show on one chart.