UGA databases and Free Sites
This is a UGA Libraries database containing over 7,000 educational films and newsreels. You must be on the campus network, or use the GALILEO password or your UGA MyID, to view the films. There are several documentaries from the BBC and PBS' American Experience.
Commercial sites - Commercial sites require a subscription, and/or advertising to view videos.
Hulu - Provides free accounts or the $7.99/month Hulu Plus option.
Netflix - New users can get the first month free. Check Netflix for their current account pricing. Commercial films and TV series on Netflix tend to come and go due to contract changes. However, many documentaries can be found on Netlix consistently. Here are some suggestions of documentaries on Netflix -- worth a search to see if they are still there: Huffington Post, Top 150 from NonFics (2015). Also, many blogs and websites will run articles on these changes. A web search for "what's coming to Netflix" or "what's new on Netflix" usually turns these types of articles.
Box Office MOJO's list of top grossing documentaries - Note: Includes concert movies as documentaries