Actually he spoke at my son's high school a couple of years ago. A little further down the food chain.
Commencement 2004:
University of Pennsylvania- Bono : http://www.dailypennsylvanian.com/vnews/display.v/ART/4056acbc4429f
Middlebury College- Christopher Reeve
Berkely- Ted Koppel: http://www.dailycal.org/article.php?id=14574
Lani Guinier University of Illinois at Urbana-Champaign -http://www.news.uiuc.edu/news/03/1113commence.html
Smith College- Judy Woodruff: http://www.smith.edu/commencement/speaker.php
Cornell= Clinton
Duke- Albright
Wellsley- Toni Morrison: http://www.wellesley.edu/PublicAffairs/Releases/2004/030504.html
Hobart and William Smith: Chris Matthews