We just watched the last episode of Freaks and Geeks. (Thanks, Colin!) If you haven't seen this show, you need to. Rent it, buy it, order it from Netflix.
It was cancelled after the first season, so there are only 18 episodes, including the pilot. I thought I would be disappointed with the last episode, since when it was made they didn't know it was going to be the last epsiode ever. But it wasn't at all a letdown. It was a perfect ending actually.