The Color Purple by Alice Walker
Just read this in two days. I found it to be a quick read because of the way it's written. Using "letters" to narrate the story seemed to make things go faster; it also made it more enjoyable because you're getting the story right from the characters perspective.
Some of the parts people might find questionable because of language and the subject matter (sex!!).
I'm not usually a fan of Oprah's bookclub books (actually, knowing that Oprah supports the books usually makes me disinclined to read it) but I enjoyed this more than a Toni Morrison novel.