UFOs

The Skeptic Encyclopedia of Pseudoscience - Michael Shermer (2 Volume Set)
Quantum Leaps in the Wrong Direction:  Where Real Science Ends...and Pseudoscience Begins -  Charles M. Wynn & Arthur W. Wiggins
Quantum Leaps in the Wrong Direction:  Where Real Science Ends...and Pseudoscience Begins -  Charles M. Wynn & Arthur W. Wiggins
NOVA - Origins: Where are the Aliens? (Episode 3)
National Geographic - Naked Science: Alien Contact
The Skeptic's Dictionary: A Collection of Strange Beliefs, Amusing Deceptions, and Dangerous Delusions
National Geographic: Is It Real? - UFOs
The Demon-Haunted World: Science as a Candle in the Dark - Carl Sagan