Armchair astronomer discovers unique 'cosmic ghost' - CNN.com: "During the last year, more than 150,000 armchair astronomers from all over the world volunteered their time, submitting more than 50 million classifications."
This is the story about one amateur astronomer who made a discovery. The discovery is important enough to warrant the attention of the Hubble Space Telescope and professional astronomers. But the real story is how the discovery was made. A couple of scientists were trying to classify one million images of from telescopes. They asked for help from the amateur astronomy community.
"The public's collective wisdom -- the same principle that guides jury trials, or Wikipedia -- proved remarkably astute, Schawinski said. For example, if 33 of 36 volunteers thought a galaxy appeared elliptical, then astronomers could be confident the classification was correct, he said."
This is similar to the same process that goes on with bird counts. Professionals rely on data collected from many amateurs to determine migration patterns, habitat health, and bird population levels.
The article goes on to describe the discovery but as I said, the real discovery is that scientists are learning to rely more on the collective intelligence of people.