The most-watched show in the history of the National Geographic Channel isn't Wild, Taboo or even the longest-running documentary series on cable tv: Explorer. It's Doomsday Preppers, a show that documents the "lives of otherwise ordinary Americans" as they prepare for the end of the world. [more inside]
Fear and Loathing on the Road to Hollywood is a largely forgotten documentary about Hunter S. Thompson (previously).
"The oldest and strongest emotion of mankind is fear. And the oldest and strongest kind of fear is fear of the unknown."
Lovecraft: Fear of the Unknown - A 90 minute documentary on HP Lovecraft with contributions by Neil Gaiman, John Carpenter and Guillermo Del Toro.
Fear and Loathing in Gonzovision 1978 BBC Omnibus documentary (Google Video)