O'Bannon started his career by writing the script for DARK STAR, the little sci-fi flick that John Carpenter went on to direct. After that he wrote the screenplay for a movie called ALIEN and changed the way we precieved the horror / sci-fi hybrid, and introduced us to characters and creatures that spawned numerous sequels over the years and still continue to be popular.
After ALIEN's success, O'Bannon went on to write DEAD & BURIED, the "Soft Landing" segment to HEAVY METAL, dived into horror with THE RETURN OF THE LIVING DEAD, then back into sci-fi / horror with LIFEFORCE, INVADERS FROM MARS, the great action / sci-fi romp TOTAL RECALL, SCREAMERS, and finally BLEEDERS in 1997.
Along with his writing credits, O'Bannon also directed THE RETURN OF THE LIVING DEAD, and worked in the visual effects department on STAR WARS. If there ever was a guy who loved to create some serious sci-fi lore, O'Bannon was it--making his passing that much more of a loss.
To celebrate his life, I suggest you catch up with one of his films this weekend. Mr. O'Bannon, you will be missed.