No people in their right mind questions Heath Ledgers preformance as the joker in Batman: Dark Knight, but who could have at least tried to fill his shoes? This is especially becomen relevant because of Heath Ledgers tragic death... This is my top 5!
Number 5: Brad Dourif
Dourif is a sci-fi actor, and has had lots of different roles in everything from Fringe and X-Files to the Lord of the Rings triology where he played Grima Wormtongue. He is specializing on mysteriouse scary roles. And that is the joker in a nutshell.
Number 4: Joaquin Phoenix
Joaquin is probably best known to most of you from his last block buster "Walk the Line", the movie based on Johnny Cash life, where he played Mr. Cash himself. In my opinion, Joaquin showed in that movie, and has shown before, some great qualities and has proven to have a very unique skill for absorbing a role and make it realistic.
Number 3: Adrien Brody
Adrien Brody is most known for his role in Academy Award-winning movie, The Pianist, where he by the way did an eminent job. I think he could easily have been a success playing the role as the joker in Batman: Dark Knight too. In many ways he looks like how I portray the joker looked like before his transformation.
Number 2: Nicholas Cage
Nicholas Cage is Nicholas Cage. What more is to say? Probably the best action-actor in Hollywood after Chuck Norris (yes, even better then Tom Cruise in my opinion). As a great plus, the movie would have been an instant success even if he did a crappy job. Every movie Nicholas Cage stars in, becomes an instant cash success.
Number 1: Jim Carrey.
Disagree? Wonder why? See ANY of his movies. Mr. Gummy Face is not only an eminent actor and a hillariouse comedian, he has also the x-factor to handle such a role. To be honest, I think he could have done an equally good of job as Heath Ledger did. If not possibly even better.