Been doing a fair bit of aimless Youtubing recently, and have found myself going through clips of De Niro et al. Fascinating to watch actors get so into character that there can be basically nothing left of them that carries over between characters (Daniel Day-Lewis), or to see them visibly taking on and developing this highly complicated and deep psychology of another person over time and really thinking in character (Gandolfini). I've not watched the film yet, but have been shocked recently by this clip of Daniel Day-Lewis in My Left Foot: ?! What other acting performances would people see as being among the very best?