...is my muse. Or at least that's the excuse I'm giving for my Planet Earth addiction.
Each iteration of watching through the series leaves me jonesing to write fantasy. There is something about landscapes, interconnected systems of nature, and bizarre lifeforms that pushes that particular button for me.
Written science is my major inspiration for science fiction. Well-crafted books by actual researchers penned for popular consumption instill the urge to communicate the world's underlying dynamics through characters and plot. They also drive me to pick up journal articles to verify that I actually understand the matter at hand. Magazines such as Scientific American, Discover, Nature, and Science Weekly provide inspiration as well, though to a lesser degree.
Blue collar people are another important source of literary motivation. All of the enlisted soldiers, NCOs, and the biotech technicians from working-class backgrounds whom I've known. Some were absolute assholes, others were the among the finest human beings that I've met. A few were a mixture of both. Either way, those with blue-collar childhoods who work in technical or craft-oriented fields often carry a set of tensions between passion and professionalism, which makes them more dynamic and alive than their middle class counterparts. Autodidactic and world-traveling members of the working class are also more prone to pragmatic insights and a moderate non-ideological wisdom than people with formal educations.
All that being said, the gifted and talented also inspire. In particular, those who successfully marry abstract theory to the blood and chaos of the world. Engineers, medical doctors, research biologists, veterinarians, and competent military officers. Also, computer science people. Not just because I have several programmer friends, but because their blended and expressive mindset seems to rest somewhere on the enigmatic boundary between art and mathematics.