Bringing Out the Dead--I'm not sure how popular this is, but it seems to get overshadowed by the rest of Scorsese's catalogue.
The Hidden--Badass opening, pretty good the rest of the way.
House of Games--Supercool Mamet. Lead actress sucks, though.
The Limey--Stylish Soderbergh, starring Terrence Stamp, Luis Guzman, and Peter Fonda.
Mad Dog and Glory--Role reversal for Bill Murray and Robert DeNiro.
Manhunter--The original Hannibal Lecktor movie. Michael Mann

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Mean Streets--See "Bringing Out the Dead". SE DVD is coming out soon.
The Player--Great Altman satire with Tim Robbins as a studio exec.
Roger Dodger--Funny. Elizabeth Berkley and Jennifer Beals are great in their supporting roles.
Short Cuts--Only Robert Altman could juggle 17 lead characters so effectively.
To Live and Die in L.A.--One of Friedkin's great movies (as opposed to "The Hunted").