For me, Shadowrun really isn't so much about the cyberpunk or the magic, but the crime. The players are playing criminals, even if they don't think they are, and I believe this affects the role-play of their characters. As a result, they make decisions that I don't believe their characters would make under the circumstances, so it took me some time to alter their mindsets a bit about the kinds of characters they play in Shadowrun as shadowrunners. I do throw in the standards for the cyberpunk feel, but I made sure they got the path I wanted them to travel. Not that they can't be good guys, but they have to know which side of the law they're on, and understand that criminals tend to think in the short term, rather the long term, and tend to rationalize bad behaviors on that basis.
To that end, my list is:
Lock, Stock, and Two Smoking Barrels
Snatch
Carlito's Way
Scarface (the Al Pacino version)
Heat
Breaking Bad (the entire show)
The Italian Job
Inception
The Sting
White Heat
Double Indemnity
The Petrified Forest
Key Largo
The Big Sleep
The Big Lebowski
Harper
Most Rockford Files episodes
Kiss Me Deadly
Chinatown
The Maltese Falcon
The Man With One Red Shoe
Top Secret! (because, hey, watching a lot of these movies gets depressing)
Get Shorty!
The Usual Suspects
Reservoir Dogs
Jackie Brown
Pulp Fiction
The Great Train Robbery
Johnny Pneumonic
Max Headroom TV show (if you can still find it somewhere)
Mission: Impossible (not the movies, but the original TV show - the movies are silly)
Kojak (who loves ya, baby?)