Richard Steinberg at StoryTellersUnplugged has a great article on why writers write:
The thirty-seven writers in my address book (along with me) are a pretty diverse bunch. We live in five countries spread across two hemispheres, to say nothing of a bunch of us scattered throughout AmeriCanada. The youngest is nineteen, the oldest ninety-three. Male and female, rich and poor, gifted and self-taught; frighteningly wealthy, piteously poor, and all stages in between.
And we're all not too bright.