I'm thinking of this as a public service thread. You can spare people all sorts of grief by sharing the books that were absolutely horrible in this thread.
Timeline by Michael Crichton. What a complete failure of writing that piece of trash was. You can tell the guy is too entrenched in screenplays because many of the scenes in the book were obvious sight gags that would probably work on film but were tediously (and ineffectively) described in prose. His characters were, as usual, bland and interchangeable, but even the action was artificially generated this time. Three times he had characters say something along the lines of, "We're trapped and there's nothing we can do about it!" And several other times, he just wrote a sentence which was supposed to raise the stakes but really didn't. Example: "They were gone, and she was all alone." :rolleyes Oh, and the "surprises"? The "twists"? Every one of them was telegraphed at least 100 pages before they were "revealed". Oh, except for the completely out-of-character murder of a guy who was apparently supposed to be a horrible villain but came across as merely an ass. The punishment definitely didn't fit the crime. That scene alone would've broken the book if it had been perfect all the way to that point. But, as I've mentioned, it was faaaaaar from perfect.
For the love of all you hold dear, do not read this book.