Deep Cover would top my list of obscure neo-noirs. Scanning wikipedia's very loose list for the genre, Alphaville, The Bedroom Window (Curtis Hanson before LAConfidential), Big Easy, Drowning Pool, Eyewitness, 8 Million Ways to Die, Gumshoe, The Late Show, Medium Cool, Le Samouri, Sea of Love, Someone to Watch Over Me, Straight Time, True Confessions, Vanishing Point, Insomnia, The Man Who Wasnt There, Mulholland Drive, Out of Time, Reindeer Games, Sexy Beast, Suspect Zero, Tell No One.
Special credit to a guy who i believe really wanted to be the 21st C Bogie before Tony Stark found him in rehab. Robert Downey Jr did two great turns in neo-noirs - Kiss Kiss Bang Bang & The Singing Detective before giving up
And of course, i'll remind folks of the movie i'm always reminding folks about - The Long Goodbye, the true daddy of the genre
ETA: one of the reasons Deep Cover tops my list is that it was the fightin' fave of one of my Albq pals, a drunk named Steve who claimed to have gotten a DUI once on a rider mower, interrupted his wedding vows with a laughing fit (i, the best man, caused it by doing a Stevie Wonder headroll cuz the preacher peppered his remarks with the phrase "bringing sunshine into each other's lives" too much) and would run out on the field at Dukes games anytime i offered to put up the bail. if my gang were all bored in a bar, all we'd have to do is mention Deep Cover and Steve would breathe raves str8 into the face of anyone who hadnt seen it and fight anyone who'd say a word agin it. it was a good flick, but thinking of Steve while watching makes it great.