"Star Trek: The Next Generation" premiered my first year of grad school, and the last episode aired my last year. It bookended my career as a student getting a PhD in astronomy, and so it has personal meaning for me. Also, I simply loved the show. And I mean love like grown-up love; I accepted its faults as well as the times it exceeded the sum of its parts.
It starts off a little goofy and fun, and ends really quite warmly. They seem like genuinely nice people -- and if you read Wil Wheaton's Memories of the Future you'll find out they really were. That's nice to know.