From a recent article in Forbes:

The writer-director-propagandist has earned every penny and Euro of his boodle. Moore's last three filmed diatribes -- "Bowling for Columbine," "Fahrenheit 9/11" and "Sicko" --h ave amassed more than $300 million in theaters worldwide, and loads more on DVD; and "Fahrenheit" is, by a long stretch, the top-grossing documentary of all time.

P. T. Barnum was right.