One of the most respected English language experts. He doesn't sound like your average ivory tower dweller, though.

http://www.youtube.com/watch?v=v7WSzxQ0nX4&feature=related
http://www.youtube.com/watch?v=Ihx5B8vkaQA&feature=related
http://www.youtube.com/watch?v=_8qOC6PJGvA&feature=fvwrel