Terry Gilliam's "The Imaginarium of Doctor Parnassus" stars Ledger as a slick-tongued man who falls in with a mysterious troupe offering a portal to fantasy worlds.
Ledger died from an accidental drug overdose after completing the real-world portions of the film. Gilliam finished the film with Johnny Depp, Jude Law and Colin Farrell taking Ledger's role in three trips to make-believe realities.
Ledger was also honored at the Oscars in February, when he was awarded Best Supporting Actor for his role as the joker in "The Dark Knight." His family accepted the trophy.
Ledger's father, Kim Ledger, said the award "would have humbly validated Heath's quiet determination to be truly accepted by all you here tonight, his peers within an industry he so loved." Sister Kate Ledger told the audience the honor will go to "your beautiful Matilda."
"Dark Knight" director Christopher Nolan, who accepted the trophy, said the award came with an "awful mixture of sadness but incredible pride" and said that Ledger's untimely death represented "a hole ripped in the history of cinema."
"He will be eternally missed, but he will never be forgotten," Nolan said.
Ledger has also been honored by several film critics associations, including the Los Angeles Film Critics Association and the Boston Society of Film Critics. He also won Critics' Choice, People's Choice and Screen Actors Guild awards for the role.