Hmm I'll participate here. There are a lot of characters from a lot of different media that I have liked over the years; however, one that I keep coming back to is Sydney Carton from A Tale of Two Cities. I read the book a long time ago, so I don't remember every detail, but I have never forgotten the major details of his storyline. Basically, I'm a sucker for self sacrificing characters.
Sydney constantly sacrifices himself for his friends and those he loves. From failing law school because he did his friends homework but not his own, to being his friends assistant to make his law firm the best in town, and even giving up his own life to safe a man the woman he loves is in love with, Sydney almost never does anything that benefits himself more than it benefits his friends. This is, to me, an ideal characteristic to have. It falls in line with a lot of aspects of my life, even if it is taken to a more extreme level than I ever have had to go to.