30. Eaters of the Dead by Michael Crichton
I was a big fan of Michael Crichton books in high school, but when I checked this book out from my high school library I found that I couldn't get past the first page. I couldn't pronounce any of the names of people or places and was utterly lost. Years later I watched "The Thirteenth Warrior" and found out that it was based on this book. (Great movie, by the way). I found out my dad had tried to read this years ago too, and was also unable due to the fact he couldn't figure out if it was supposed to be fiction or non-fiction. This time I was able to get through it (I was able to figure it out more easily after seeing the movie) and it was a great book. The best part was the afterword, in which Michael Crichton explains the reason for writing the book (a bet that he couldn't write an interesting Beowulf story) and states that later when going back over the book, he couldn't tell which footnotes he made up and which ones were true. Which was funny because I couldn't tell either.