I never really understood why Letterman even had his own show. His whole "approach" to interviewing guests is to basically pretend that he doesn't understand whatever it is they do to get them on his show.
Like the other night when Liv Tyler was on, the only thing he basically said was "is an elf a hobbit? Is a _______ a hobbit? What is a hobbit??" It was just stupid. Liv looked hot though.
The best letterman show I ever saw was when he had the shingles and Vince Vaughn was guest hosting. I don't even remember who the guests were, but Vaughn was FREAKING HILARIOUS!! I love that guy's sense of humor...