Lucifer's Hammer

Very good book about the end of the world due to a comet impact. It starts off with life before the comet, then during the impact and then the struggle for survival starts. Lots of characters with their own side story so it is sometimes difficult remembering who is who. The story mostly focuses on the area of Los Angeles (the rest of the world isn't quite forgotten, but they only get short descriptions of destruction). Now I do wonder why this was never turned into a feature film.