Verified answer

The ones I can recommend are the rare, scientifically informed ones that talk about looking for ET life, rather than UFO-Eric von Daniken stuff that's taken over the History Channel. What are the people on Ancient Aliens taking?

There's a good one on youtube featuring Carl Sagan, Stephen Hawking and Arthur C. Clarke.

1. Louis Theroux's 'Weird Weekends' UFO's

http://www.youtube.com/watch?v=pDJQQH6ytOU

2. I Believe in UFO's by Danny Dyer

http://www.youtube.com/watch?v=Dxc1W8exe7g

3. UFO's The Secret Evidence

http://www.channel4.com/programmes/ufos-the-secret...

In this two-hour special, journalist Nick Cook embarks on a journey into a world of mystery and deceit. After 20 years of investigating some of the strangest and most secret military aircraft to take to the skies, Cook, a British Aerospace specialist, applies his expert knowledge to the fantastical realm of UFOs, close encounters and tales of alien abduction.

That's kind of an oxymoron. Documentaries usually deal in facts.