2. March of the Penguins (2005)
The rare documentary that was both a critical and commercial smash, this National Geographic film, directed by French filmmaker Luc Jacquet, went on to win the Oscar. Shot over the course of a year in Antarctica, the footage shows the astonishing existence of Emperor Penguins, whose breeding grounds in winter ends up being 60 miles of ice away from the ocean where they can hunt for fish. The narration by Morgan Freeman shamelessly anthropomorphizes the birds, but there's no denying the power of the footage.