George Balanchine was the greatest artist of the 20th Century, by far. I got to see a lot of his work when it was still being performed under his direction. I knew many people who knew him, professionally or in more personal ways, but I never met him myself.
Once, in the lobby of the State Theater, during an intermission in a program of The New York City Ballet, I was looking for a friend and my eyes lighted upon Balanchine, standing about ten feet away from me. Our eyes met for a moment, I nodded slightly and he nodded back, slightly. Then I looked away and walked to a different part of the lobby.
I consider this one of the most thrilling moments of my life.