After being an assistant to Todd Phillips on "The Hangover," Joseph Garner made a huge leap -- with the help of executive producer Zach Galifianakis -- to documentary filmmaker. Wondering whether man can live by Craigslist alone, Garner traveled the USA for a month with just a computer, a phone, and the website Craig Newmark created as a virtual flea market. Who inspired Garner? "If you had to look at a documentary filmmaker's entire body of work, for my money, you can't beat Errol Morris and Joe Berlinger," Gardner told Yahoo! Movies. "Two of the greatest voices in documentary filmmaking [that] consistently find interesting subjects and compelling ways to tell their stories. Since it would be too hard for me to choose a single one of their films, for the purposes of this list, here are my top five first-person documentaries:"