Joaquin Phoenix's turn from actor to rapper is getting more bizarre by the day. On David Letterman's "Late Show" Wednesday night, the Two Lovers star seemed completely out of it, staring off into space, answering questions with one-word answers and, at one point, sticking gum on the edge of Letterman's desk. This guy is the best! He is out of his mind! Late Show Wheres Joaquin Phoenix ?