But as lucrative as sci-fi is on the big screen, the genre has found even more success on television. From "Star Trek" to "Lost," there is no short supply of space-set or time travel-y TV.
As "The X-Files" reboot approaches, here is a definitive ranking of the best sci-fi TV shows ever made. (Spoiler: "SeaQuest DSV" isn't one of them. Sorry, Darwin fans.)