What's the scariest book you've ever read?

I was able to read once a paranormal psychology book which is not really intended to borrow it from the library. But due to my curiosity, I really asked for assistance from my friend who happened to be a library assistant at the same time. So I bought it at home and to my surprise, I wasn't able to sleep at night during that time. Too bad for huh hehehe...

The scariest book I read up until now has been "Misery" by Steven King. I am now on the last 100 pages of "Duma Key" by Steven King. Last night I actually slept with the tv on because that is how much this book is freaking me out. I have a 10 year old daughter who asked me if she could read it when I was done and I said sure; that's when I was up to page 250 or so... Since then, I have said no way. The book is so vivid with the images you see as you are reading it, that as soon as I am done, I am getting rid of the book. Don't get me wrong, it is really good, but I am not a horror book reader and "Duma Key" definately gave me the willies. I will be sleeping with a night light on tonight, especially if I complete the book tonight before bedtime.