Chances are, this is what you want to see. This Flash presentation combines Lawrence Lessig's original 243-slide presentation (on the current state of intellectual property and its ramifications on creativity and culture) timed against the audio of his OSCON 2002 keynote address.
[Note: If you're having strange audio on Linux or Mac, trying using the fast forward/reverse buttons, which may clear up the sound. There appear to be some strange intermittent bugs with the MM Flash players and the Sound object interaction.]
MP3 Audio [7.2MB, 31'40, 32kbps mono] - Stream with M3U
If you just want the audio, say to listen to over and over (or for any other reason, of course).