Favorite acting performances in a movie?

It's Vince Young wearing a trenchcoat behind a computer screen.

And anyway my favorite acting is Quentin Tarantino..In whatever movie he's in. What an inspiring actor. Very humble too. He got robbed of an Emmy in Pulp Fiction.

 

Tim Blake Nelson and John Turturro as Delmar O'Donnell and Pete Hogwallop in O Brother Where Art Thou.

 

Val Kilmer - Doc Holiday (tombstone)
Dennis Hoffman - Rain Man
Anthony Hopkins - Silence of the Lambs
Edward Norton - Primal Fear
Edward Norton - American History X
Robin Williams - Good Will Hunting
Paul Newman - The Verdict
Daniel Day Lewis - There Will Be Blood
Kevin Spacey - Verbal Kint (Usual Suspects)
Hugh Jackman - The Fountain
Leandro Firmino da Hora - Lil Ze (city of god)
Brad Pitt - Snatch
Forrest Whitaker - Last King of Scotland
Leonardo DiCaprio - Basketball Diaries, The Aviator, and others.
Don Cheadle - Boogie Nights


As for Heath Ledger... He was better in Monster's Ball, Brokeback Mountain, and maybe even 1 or 2 others before The Dark Knight.

 

Since no one's said it...

Edward Norton as Derek Vinyard in American History X.
Sacha Baron Cohen in Borat and soon to be Bruno.


Okay, so right as I posted someone else mentioned American History X.

 

William H. Macy as Sheriff Chappy Dent in Happy Texas
Will Smith as Chris Gardner in the pursuit of happiness
Alan Arkin as Yossarian in Catch22
Mickey Rourke as Marv in Sin City
Christian Slater as Adam in Untamed Heart
Marisa Tomei as Caroline in Untamed Heart

 

mickey rourke in The Wrestler

 

A lot of great ones have already been listed.

A few that haven't also spring to mind...

Alec Guiness - Bridge on the River Kwai/Lawrence of Arabia
Juliet Binoche - Trois couleurs: Bleu
Peter Sellers - Being There (but really, just about anything he did would qualify)
Michael Redgrave - The Browning Version (the original)
Brando - On the Waterfront
Peter Finch - Network
Liz and Dick - Who's Afraid of Virgina Wolf
Mieko Harada - Ran
Robert Shaw - Jaws

 

Paul Newman-IN EVERYTHING.

 

I almost said newman - anything when mentioning The Verdict.

 

Ian McKellen, gandalf in the lord of the rings trilogy

Clint Eastwood, the good the bad and the ugly

Russell Crowe, gladiator

Matt Damon, jason bourne in the bourne trilogy