Fast Food Nation.
I thought it was a very good book. Sort of like the Jungle for our generation, albeit more documentary style and less fictional narrative. I still go to fast food restaurants, but less often than before. One thing that I thought was pretty cool, is the coverage of fast food restaurants that are atypical in the industry like In N Out. In N Out is much better fast food than other places.
Taco Hell is the worst, it is even worse than Mac-Donalds.