The pro bono spots first started with Woody Allen, Barbara Walters, Ben Stiller, Kevin Bacon, Robert DeNiro, Billy Crystal, Henry Kissinger, and Yogi Berra. BBDO/New York has now added Christopher Walken, Al Roker and Vanessa Williams to the roster.
You can check out all the spots here:
note : domain has been bought by a korean portal company and is not worth clicking anymore. this was after all January 21, 2002 - eons ago in web-time