I was watching the late late show and this awesome guitarist came on. They said she was "cathy king". I searched for this and found an older woman, obviously not the same artist. I searched some more and eventually found a blog where someone else had done the same thing. So, if you search for Leno, Letterman, Late Show, Late Late Show and Cathy King, or Conan O'Brien, this page is for you. It is not Cathy King, but Kaki King. She plays fingerstyle guitar with hammer-ons and plenty of tapping and harmonics. Awesome indeed!