8) The Violent Years
Though perhaps best remembered by MST3K fans for the infamous "women gang-rape a dude" scene, The Violent Years is an Ed Wood-directed exploitation flick about a spoiled rich brat who turns to a life of crime. Said life soon brings her to a sad end, dying in childbirth (see aforementioned scene) following a shoot-out with police. Oh, and because the parents did such a lousy job with their dead daughter, the preachy judge at the end refuses to let them adopt their grandchild. Thought not shown onscreen, it's safe to assume the parents offed themselves shortly thereafter.
7) The Brute Man
Like Andre the Giant and Richard "Jaws" Kiel, titular actor Rondo Hatton had acromegaly, and the filmmakers exploited his condition by casting him as a disfigured murderer. That should tell you all you need to know about this movie. The Brute Man is a former college football star who, through a random series of circumstances and mostly due to his own actions, ended up mixing some chemicals that burn his face badly. So he responds by strangling anyone even tangentially related to the incident, though again, he was the one who mixed the wrong chemicals. In the midst of his crime spree he befriends a blind woman and then tries to kill her--not a real sympathetic character, that Brute Man. Fortunately, he gets killed instead. Nobody really wins and life seems pointless. The cinematography is as dark as the story.
You may be surprised to see Shakespeare's most critically acclaimed play on this list, but let's face it -- Hamlet is depressing. It's about a guy who: finds out his uncle murdered his father and married his mother; kills his girlfriend's dad and then watches as she goes insane; has his two best friends killed; and then, after hours of dawdling, finally (spoiler alert!) kills his uncle and everyone else before dying himself. Now, take that story and film it in the darkest, barest setting you can find, use tar for film stock, and for the final touch, cast it entirely with soporific Germans (oh, and then dub the whole thing back into English). By the time the movie's over, it'll have you reaching for the ear-poison.
5) Parts: The Clonus Horror
The Clonus Horror made the news a few years back when people noticed the 2005 turd The Island had a very similar plot, and in fact the producers of Clonus Horror sued and got a settlement from The Island producers. Never was so much fuss made about two such unworthy movies.c The Clonus Horror is the story of a dim bulb who slowly realizes something is very weird about the world he lives in. He eventually discovers that he is in fact a clone, part of a secret complex of clones created solely as organ farms for rich individuals. Once they reach adulthood, the clones are killed and freeze-dried so as to preserve their organs in prime condition. Escaping the complex, the nameless Hero Clone finds a retired journalist to help him and eventually locates his "father," the man he's cloned from. Long story short, the bad guys running the clone farm close in, Hero Clone's girlfriend is lobotomized, Hero Clone himself is murdered and the elderly journalist and his wife are blown up(!). The ending suggests the bad guys and their crimes will be revealed to the public, but anyone we even slightly cared about is dead. So, kind of a downer.