I'm actually a really *huge* Star Trek fan! For those that don't really know, Klingon is a language from the show with actual syntax and grammar. I could talk for hours and hours about Star Trek, but I suppose what really grabs me is that the various shows all show something worthwhile. Human beings that work to help everyone indiscriminately, while also showing various facets of history and societies. For instance, if we just take race, the "Cardassians" are a militaristic race, the "Ferengi" are prime time capitalists, the "Bajorans" the spirituals that were forced to become warriors. The "Klingons" of course, warriors for honor but throughout the shows, we see how absolute power (in their "high council") keeps corrupting.
And if we go further than that, we see Star Trek promoting inclusivity, i.e. with the first colored woman starring in a show on TV. It promotes multicultural values, including the first interracial kiss on TV! The various technologies (cell phones, anyone?) that Star Trek envisioned and inspired are plenty.
There's so much more, but since you didn't specifically ask, I'll spare you more!
Note: I'm talking about the older shows (ST: TOS, ST: TNG, ST: DS9, ST: VOY and ST: ENG). I'm not talking about the new shows/movies - since they seem to be missing the original Roddenberry vision (humanity to all) and that's sad.