..As much as I could get hated for this by the Potterhead community, my favorite character out of any character ever created is:
Severus Snape I've never had a character that I was so emotionally invested in on all ends of the scale. I used to hate this character so much, and then I went to the complete other end of the scale and love him by the end of the Harry Potter series. I've felt such an array of emotions over this character. Also, in the movies he's played by my favorite actor (Alan Rickman) which makes him even more awesome for me!
Because this character has moved me so much he's always stuck with me, and I'm fond of him enough more than any other character to call him my all-time favorite.