Wynton Marsalis does some excellent, beautiful work. You can hear some of his music on his Website — check out the podcasts. Update (6-12, 10:20 AM): I like his quote:
The jazz band works best when participation is shaped by intelligent communication.And, of course, a search on YouTube turns up quite a bit. Yahoo Music also has a few Wynton video and audio recordings. Thank goodness for the mathematics, science, technology, business, capitalism and thought and logic that makes his music so accessible.