This is a book that I started reading as a kid but didn't finish. I remember it involved a young girl who lived in a society underground where there is no light. None who lived there have experienced sight before. Their time is strictly regulated by clocks. I think I remember the clocks being described as talking of demanding things of them with the chimes. The chimes call everyone back in. One day, she doesn't come in, and meets something either on the surface or outside and it shows her light. Soon she sneaks out often to experience this new sense with the forbidden creature. That's about as far as I got. This would have been around 2004, but the book was not brand new at that point.
Before anyone asks, this isn't the City of Ember. I read that as a kid too and would have remembered.