In the closing credits, the charwoman (an animated caricature of Carol Burnett) is seen in the bottom left-hand corner of the screen mopping the floor. As the credits roll she suddenly turns and notices them and for the rest of the sequence she leans on her mop and watches them move from bottom to top (except for a brief pause to scratch her behind).
At the end of most shows in the early seasons, the announcer said "This is your announcer speaking."