some really great ones mentioned above!
These might not have been mentioned...
Testament (1983) - the nuclear war movie that was everything that "The Day After" should have been. Testament has such a powerful narrative and characters that were well written. In comparison "The Day After" was just another contrived disaster melodrama with stock characters and predictable arc. See Testament. That film still makes me cry.
Koyaanisqatsi (1982) - a visually arresting film without characters or dialogue. I don't know if it has the same impact today as it did back then, but I would say that much visual exposition today was influenced by this movie. This film should be a boring waste of time but I couldn't take my eyes off it.
Nineteen Eighty Four (1984) - I really love the look and pace of this movie. Acting was poignant and beatiful.
The Singing Detective (1986 BBC miniseries) - one of the best miniseries I've ever seen to date. Michael Gambon is just superb. It's mystery, comedy, musical, psychological thriller and very thematically, psychologically and emotionally rich narrative. Based on the semiautobiographical treatment by Dennis Potter about a mystery writer with severe psoriatic arthropathy who finds himself hallucinating in a hospital ward. Don't watch the 2003 Hollywood version ... watch this one. You can find it posted on YouTube. Just watch the first episode and see what you think.
Live and Die in LA (1985) - great cop film with standout performance by Willem Dafoe. I've watched it again and again.
Extreme Prejudice (1987) - I've watched this Walter Hill action flick many, many times. It's often overlooked but it's got some great moments and stands up to multiple viewings IMO.
After Hours (1985) - small scale Scorsese film that's just plain fun to watch. The character reminds me of myself many years ago, and I have had more than one night like his (not as extreme, of course, but along similar lines.) in strange neighborhoods.
My Dinner With Andre (1981) - just wonderful to hear this discussion. Nothing profound. Just great discourse.