Found this Snopes entry linked on a Metafilter thread about the lasting impact of M*A*S*H. I always credit watching that show in syndication every night at dinner with making me wanting more out of TV and narrative media:
Producer Larry Gelbart on the night of shooting the last scene of that season:
“I did not want to rehearse it; we would shoot it only once. Then, Gene and I took the cast aside and I opened a manila envelope that contained the one-page last scene, telling them I had something I wanted to show them.
… I gave each [actor] a copy of the scene to read to themselves. Each had a different reaction.
“F**king brilliant,” said Larry Linville.
“You son of a bitch,” Gary said to McLean. “You’ll probably get an Emmy out of this!”
After Gary [Radar] finished reading his message, there was a hushed silence on the set as B.J.’s camera panned the stricken faces of the cast, and then someone off-camera accidentally let a surgical instrument drop to the floor. It was perfect, that clattering, hollow sound, filling a palpable void in a way that no words could. ”
Full entry on Snopes http://www.snopes.com/radiotv/tv/mash.asp