I've always scoffed at Bigfoot theories, but then I stumbled across "The Missing 411." Apparently, there's an ex-cop who has been investigating the bizarre disappearances of hundreds of people in national parks. People go missing out of thin air, or pop up in locations that are just physically impossible. The guy (David Paulides) even created a documentary out of this about a year ago. Here's the trailer:
For some reason, I found it kinda spooky. Apparently David Paulides now travels around the country giving talks on the subject. He specifically won't speculate about outlandish conspiracy theories, but he presents some really compelling data compiled from police reports, etc.