There are some books that have the most perfect opening lines.
My favorite is still from one of the Dresden Files books (Blood Rites, I believe), which starts off with, "The building was on fire, and it wasn't my fault."
The book I just picked up has a great opening as well - not even the first line, but the first page: "Once upon a time, an angel and a devil fell in love. It did not end well." I have no idea what this book is about, but I need to find out now. Did it not end well because angels and devils can't get along? Or did it not end well because it was forbidden and now everyone's out to get them? Or something else entirely?
I suppose I will find out. If you are interested, it's The Daughter of Smoke and Bone by Laini Taylor. I found it on a random library wandering and thought the title was cool.