Well I wasn't as hooked as quickly as with the show 24, but nonetheless I am now a big fan of Joss Whedon's Firefly. How to describe the show? Well, imagine that the rebels had been crushed by the Empire, but that Han Solo lived and returned to smuggling.
Incidentally, if you do decide to give it a try, don't you dare rent the movie first. You need to watch the television episodes in order (there are four total discs--the evil capitalists cancelled the show in the first season) and then watch the movie, Serenity.