James Cameron (lost some cool points because of Titanic)
Billy Wilder
Sam Peckinpah
Walter Hill
Sergio Leone
John Ford
Howard Hawks
Clint Eastwood
George Miller (Max Max 1 and 2 are great, Beyond Thunderdome blows)
Robert Rodriguez (always enjoy his work except for Spy Kids)
Quentin Tarantino (might as well throw him in here too)
John McTiernan (Predator is not my favorite film despite my username)
Christopher Nolan (Memento, The Prestige, The Batman franchise films are good, but they ain't as great as people make them out to be)
Michael Mann
Oliver Stone (his older work, new stuff not so much)
Ridley and Tony Scott (probably prefer Tony over Ridley)
Francis Ford Coppola (The Godfather films are good, but more because of Apocalypse Now)
Stanley Kubrick
Martin Scorsese
John Carpenter
Cohen brothers

I'm not that much into horror or zombie flicks but,
Wes Craven (could do without all those damn Scream sequels)
George Romero

In regards to Michael Bay, I enjoyed Bad Boys and The Rock growing up. The Transformer films are fun to watch sometimes. The effects and battles are the only thing going for them.

No Danny Boyle? Blasphemy!

Trainspotting is about the only one of his I really care for.

Also I forgot to put David Fincher in the list.

At this point in my life of movie viewing one of my favorites has to be Johnny To. I loved Exiled and running out of time and Breaking news was awesome.

"Bad Boys" was enjoyable if dumb, while the sequel was extremely dumb and not very enjoyable.

Not sure you can say he "launched" Brad Pitt's career when the first movie they made together was "Seven". Pitt's career had long since taken off by that time (he had starred in "A River Runs Through It", "Interview with the Vampire", and "Legends of the Fall", all of which preceded "Seven").

Also, surprised nobody's mentioned Paul Verhoeven yet. Even though he's made some really bad movies ("Showgirls"), he also made "RoboCop" and "Starship Troopers".

Showgirls is just mainstream pornography.

Paul Verhoeven is an objectively bad director. His only "good" movies were RoboCop, Total Recall (both mindless enjoyable action films), and Basic Instinct, which was completely average and only notable for showing Sharon Stone's hoo ha. Starship Troopers was laughably retarded (he didn't even read the original book), Showgirls and Hollow Man (didn't see either of them) were savaged by the critics and are both pop culture punchlines. Everything else he's done is not notable and/or Dutch.

If you say that Danny Boyle is an objectively bad director, Robert Carlyle will smash a pint of beer into your face and then continue to kick you in the face will you're down on the ground, crying in pain.

I really doubt that but as far as I know his only stinker was The Beach. Trainspotting and 28 Days Later were really good, I haven't seen Slumdog Millionaire or Sunshine or Millions, but I've heard nothing but good things.