I know this is a couple days late, but thinking about Thanksgiving brought this 1979 exchange from "The Tonight Show Starring Johnny Carson" to mind. Johnny had forgotten that Doc was no longer married, and Doc's remarks drove Johnny to tears of laughter.
EDIT (8/15/2014): Here is the video from Johnny Carson's official YouTube, so this one should stay up!
EDIT (8/15/2014): Here is the video from Johnny Carson's official YouTube, so this one should stay up!