Danny Elfman is incredibly well-known, even if you don't know him by name. He's most famous for his work with Tim Burton. Elfman has, to the best of my knowledge, scored every Burton movie with the exceptions of Ed Wood and Sweeney Todd.
Elfman is also responsible for the now-famous opening piece on The Simpsons.
His filmography is extensive and includes work with Sam Raimi and, alledgedly, the forthcoming remake of horror-classic The Wolf-Man.
Elfman's music can best be summed up as a season - Autumn. The dark nature is best accompanied by a chilly, clear night with light cloud cover and a deep, misty wood.
To hear one of his lesser-known compositions, check out the video in this post, featuring the score from Black Beauty.
In 2006, Elfman branched out from movies, penning Serenada Schizophrana, his first major compostion not to be written as a soundtrack, though it was later featured in the IMAX movie Deep Sea 3D. Below is the track "I Forget" - the only track with vocals, all of which are in Spanish.