Roger Waters and guests performing Comfortably Numb on July 21, 1990. The one night only performance of The Wall commemorated the fall of the Berlin Wall.

From the wiki:

The concert was staged entirely at Waters' expense, and while he subsequently earned the money back from the sale of the CD and video releases of the album, he has donated all profits past his initial investment to World War Memorial Fund for Disaster Relief.

Be sure to visit the wiki link to put names to all those faces in the video. This is Late Late Nite FireDogLake, where off topic is the topic ... so dive in.