The following is a list of documentary films and television series recommended by /tv/. [=WIP/Feel free to contribute=]
Ecology
Generally regarded as nature porn, and much like porn, it is ALWAYS better in HD. Click the mute button and put on some Yanni if you don't feel like getting lectured on why human beings are evil and the rest of the animal kingdom are the victims in this space opera called planet Earth. The following is a list of nature documentaries worth checking out. Sir David Frederick Attenborough is always related.
Albatross about to have his day ruined by a hungry Great White, in glorious full HD.
Planet Earth (or the child-sized Disney version, Earth), which is a rerelease in HD of edited footage from the obsolete series The Blue Planet.
The "Life" series, by Attenborough, of which The Life of Mammals (2002) is the pick of the litter.
South Pacific (also known as Wild Pacific in America, and redubbed with narration by Mike "I'm a Bear" Rowe himself, who honestly did a pretty damn decent job for a redub of a series that was already in english. Seriously, Discovery Channel, what the fuck?)
Nature's Great Events (also known as Nature's Most Amazing Events in America, also redubbed but this time it's highly recommended the original narration by BBC's Attenborough be obtained in lieu of the less eloquent Discovery counterpart.)
Galapagos, narrated by Tilda "Ice Cold Queen Bitch" Swinton. It does a good job at making you feel like shit for being part of the human race, while stunning you with beautiful landscape imagery that seems like some distant world unlike ours.
Life, narrated by Attenborough, sadly isn't worth checking out if you've already seen his earlier stuff. It seems BBC got lazy and reedited yet again the same HD footage we got from TBP and PE. To add insult to injury, Discovery Channel decided it would be appropriate to redub the narration, this time with none other than fuckin' Oprah. Suffice it to say, she went back to bribing bored housewives with more gas-guzzling minivans than she could fit under her studio seats.
Astronomy
Cosmos, by Carl Sagan. This shouldn't need a synopsis. Hell, it shouldn't even be on this list, you should have already watched it 10 times over and surrendered your ethereal being to captain the starship of the imagination.
Journey to the Edge of the-OH FUCK DID THAT JUST HAPPEN?!
Journey to the Edge of the Universe, extremely underrated, underground, and underradar'd. Supposedly even better if you toke prior to hitting Play.
IMAX's Cosmic Voyage, pretty good amount of theory with some nice visuals. Entry level stuff, really.
Alien Planet, narrated by Dr. Cox himself, John C. McGinley. Speculation and CGIfest about what life in other habitable planets might look and behave like. Pretty darn entertaining.
The Universe, a History Channel (I know, right?) series, now in it's fifth season. It includes a lot of dumbed down theory, a lot of people talking, and a lot of reused CGI. It lost its momentum sometime during the second season, and by now it has regressed into full speculation mode, like the rest of that channel's non-reality show lineup.
General Interest
Bowling for Columbine, Michael Moore's best.
Supersize Me, something about how eating greasy fast food and NOTHING BUT will turn you into a hambeast. Thanks for the sage advice, guy!
King of Kong, docu about a couple of nolife neckbeards from old /v/ trying to one-up each other.
The Bridge, about a series of suicides on the Golden Bridge. GRIMDARK AS FUCK.
War
Battle 360 - Details of assorted battles with cgi dramatizations.
Battlefield Vietnam, In depth overview of key battles of the Vietnam War, probably the best Vietnam documentary that focuses on the actual battles and not the political strife.
Carrier (pbs miniseries), Documents life aboard a modern Aircraft Carrier.
Civil War Journal, Gives detailed personal accounts of the civil war drawn from the journal entries of it's participants. Quite good.
Conquest, Generally a fun show about various weapons from history, host can veer into douche territory but doesn't ruin the show.
Clash of Warriors, Details selected battles between some of History's greatest commanders.
Clash of Wings, In-depth documentary about the key aircraft used by all sides during WWII.
Decisive Battles of the Ancient World, Cheap documentary that uses the Rome Total War game engine to illustrate troop formations and maneuvers of various important battles from the Ancient World. Does contain good information if you can get past the producer's brazen stupidity.
Empires (pbs), Narrated account of various important Empires from throughout history, mostly pre-modern.
Greatest Tank Battles, Theatricalized accounts of selected key battles of WWII, features a large amount of interviews with those who participated.
Ken Burns' Civil War, Civil War documentary that set the standard for all other Civil War documentaries.
Nazi Collaborators, Narrated accounts of individuals who collaborated with Nazi occupying forces to subjugate their host nations.
Russia's War - Blood Upon the Snow, Very detailed & depressing account of Russia's experiences before and during WWII. !Warning!, if you don't like very dry factual documentaries, avoid this one at all costs.
Secrets of WWII, standard documentary about various secret operations of WWII by The Axis & The Allies.
The 10,000 Day War, Depressing narrative about the Vietnam War viewed through the political lens. A standard.
The Boer War, Very good documentary about a pivotal yet neglected conflict from the turn of the 20th century.
The First World War, Standard series about The Great War.
The English Civil War, Decent account of Mr. Cromwell's exploits.
The Nazis, Narrative account of the small political party that seized the reigns of power in a first world nation at the worst possible time in the worst possible way.
The Revolution, Narrative account of the American Revolution. Very high production values.
The War of the World, Narrative account of the First World War. Good production values.
Tales of the Gun, Extensive series that focuses on the back stories of History's most influential firearms.
Victory at Sea, The Godfather of war documentaries.
Vietnam in HD, Narrative account of the Vietnam War, features very high quality footage of battles and various events relating to the war.
War and Civilization, General series about warfare & it's conductance with examples drawn from around the world and various periods of history. Narrated by Walter Cronkite.
War of the Century, Narrative account of the eastern front during WWII. Rich production, and quality interviews with participants & knowledgeable historians.
Wings of the Luftwaffe, Well-worn series detailing the various aircraft of the German Air-force during WWII
Wings of the Red Star, Counterpart to the above detailing the aircraft of the Soviet Air-force during WWII.
WWI in Color, Good series with impressive colorized footage of WWI
WWII in Color, Same as above dealing with the second war.
WWII in HD, Similar to above with even higher quality footage of the war and very high production values.