For me, either John Locke or Sylar.
Both men who try to understand who and what they are. "Why are we here? What's the meaning to all this?" Maybe the fact that I find them so interesting says something important.
What about you? From any genre of television, who are your favourite characters? The ones you'll [i]never[/i] forget?
-
John Locke and Jack Shepard (who I consider two halves of the same character) or Dr. House.