Next time you're at the video store, take a fly and rent a movie by one of these great "forgotten" directors: Ernst Lubitch, one of the three or four greatest comedic directors of all time. "To Be Or Not To Be" - Where Jack Benny and Carol Lombard are actors in a Polish theater troup during WW2 and stage a comedy about Hitler. This movie was made in 1941 and is lightyears ahead of Mel Brook's "The Producers." "A Shop Around the Corner" - IMHO, probably the greatest romantic comedy ever made. "Trouble in Paradise" - the original romantic triangle flick.
Then there's always... you know... what's his name... damn, it's on the tip of my tongue. He made... crap, what was that movie. Whoever he is, he's the most forgotten director EVER.
For anyone who would actually visit this thread, this may be an obvious choice, but to the general public it won't be. Terrence Malick. His films are incredibly visionary, thoughtful and beautiful in a dream-like way. Most cineastes are familiar with Malick's ouevre -- Badlands, Days of Heaven, The Thin Red Line -- and popular awareness of him grew when TRL was released and nominated for best picture after Malick had taken a 20-year layoff. Still that was five years ago (how time flies!!!!) and I'm sure there are people who use this forum who are unfamiliar with his work. How about the old Gus Van Sant, back in the days before aliens abducted him and forced him to make crap like Good Will Hunting? He's sure as heck long gone and forgotten, even to Gus Van Sant. Heck, especially to Gus Van Sant.
Wholeheartedly agree with all the Lubitch choices but this one especially: How about Bill Forsythe? While his later stuff has less comedic appeal, Gregory's Girl, That Sinking Feeling, and Local Hero all manage to perform the small miracle of being affectionate without being sappy.
Alexander Mackendrick, who's most known for The Sweet Smell of Success, made several other really good dark comedy/satires in the same noirish vein, like The Man in the White Suit and the Ladykillers. I went to a retrospective of his films a couple of years age b/c Sweet Smell is one of my all-time favorites and was blown away how well shot and consistently thought-provoking the above two movies were. Interestingly, if I remember correctly, Sweet Smell was such a commercial disaster that it basically ruined his career as a director.
One would be Robert Rossen. His two best known works are, All The Kings Men, and The Hustler. He was 58 when he died, so I'd like to think he had another great film in him. Also was blacklisted, and then named people. So is life's story is interesting as well. Another who's body of work was tremendous, but people don't always put on their off-the-top-of -your-head short list, his Hal Ashby. Before the drugs really messed him up, he had this run of films: Being There Coming Home Bound for Glory Shampoo The Last Detail Harold and Maude In addition, he was a tremendous editor: The Thomas Crown Affair, The Cincinnati Kid, The Russians Are Coming, The Russians Are Coming. In The Heat Of The Night. I've been doing some reading on this period, so it's still fresh in my head, and a lot of people in the industry feel that it was Ashby, not Scorsese, Altman, Coppola, etc., who was the goods-the most talented of the lot.