In the vein of powerful commercials.  Here is a new one I saw today.

http://www.transbuddha.com/mediaHolder.php?id=1208 (I had trouble with this in Firefox, it works with Internet Explorer)

The above is a public service announcement from Médecins Sans Frontières on the impact of HIV/AIDS in Africa.  I learned about this from an amazing blog/website www.worldchanging.com http://www.worldchanging.com/archives/003941.html