* The next-to-last episode, "The Clip Show". At the end, the montage of best moments, bloopers, and behind the scenes footage of the cast members joking and laughing together, while Good Riddance (Time of Your Life) by Green Day plays over it, ending with the cast taking a deep bow for the audience, hand-in-hand... The last slow pans of the quiet, deserted sets of Jerry's apartment and Monk's Cafe, both places that viewers were as familiar with as they were with their own real-life hangouts. Plus the phrases "I hope you had the time of your life" and "For what it's worth, it was worth all the while" .... there are simply no words to describe the exquisitely painful sheer excellence of it. For a sitcom that never had a truly serious emotional moment, it sure invoked a hell of a lot of emotion in its huge viewer share.
* George gets a brief one in the Frogger Episode. He overtly declares that the only accomplishment in his life that he cares about is a video game high score.