Ahhh heres a thread tailor made for me now. This is waaaay too hard of a question for a movie buff like myself, so I'm going to try my best to list what comes to mind. The longer list comes straight from my MySpace
Top 5
Blue Velvet
Donnie Darko
Garden State
Eternal Sunshine of the Spotless Mind
The Graduate
2001: A Space Odyssey, Adaptation, Alice's Restaurant, Almost Famous, American Beauty, Annie Hall, Apocalypse Now, Awakenings, Being John Malkovich, The Big Chill, Big Fish, Black Hawk Down, Boogie Nights, Born on the Fourth of July, The Breakfast Club, Clerks, A Clockwork Orange, Close Encounters of the Third Kind, Closer, Crimes and Misdemeanors, Dazed and Confused, Dead Poets Society, The Deer Hunter, The Motorcycle Diaries, The Doors, Dr. Strangelove, Easy Rider, Election, Eyes Wide Shut, Fargo, Fast Times at Ridgemont High, Fear and Loathing in Las Vegas, Fight Club, Full Metal Jacket, Ghost World, The Godfather, Good Will Hunting, Goodfellas, Halloween, Heathers, JFK, Kill Bill Vol. 1, Kill Bill Vol. 2, Labyrinth, Leaving Las Vegas, The Life Aquatic with Steve Zissou, Lost in Translation, Magnolia, MASH, Moulin Rouge!, Night of the Living Dead, Office Space, One Flew Over the Cuckoo's Nest, The People vs. Larry Flynt, Platoon, Pulp Fiction, Punch-Drunk Love, Requiem For a Dream, Reservoir Dogs, Rushmore, Saving Private Ryan, Scarface, Seven, The Serpent and the Rainbow, The Shawshank Redemption, The Shining, Sixteen Candles, SLC Punk!, Suburbia, Taxi Driver, The Thin Red Line, Thirteen, Three Kings, Traffic, Trainspotting, The Usual Suspects, Vanilla Sky, The Virgin Suicides, Woodstock, The Wall, Munich, Broken Flowers, Hotel Rwanda, The Last King of Scotland, The Toxic Avenger, Class of Nuke Em High.
Yeah quite a few obviously...maybe throw in Vanilla Sky in the top five. Most people hate it; I don't understand why because the film is utterly beautiful.